Setting Up A Fish Tank: Avoid These 24 Beginner Mistakes

Last Updated on 2024-05-27

If you’re setting up your first tank, then you’re going to have a million questions! Don’t worry, you’re about to have them all answered! Not only are you going to have every one of your questions answered, and a COMPLETE guide on how to setup your first aquarium!

But it doesn’t stop there, you’ll also find out about the 24 most common mistakes, common problems that occur and how to troubleshoot them, the nitrogen cycle and why it’s so important, the best fish and plants when you’re just starting out, and much much more!

So keep reading to find out everything there is to know about setting up your first fish tank.

Choosing The Right Aquarium

Before anything you are going to need to choose the right tank for your fish! If you don’t get the right tank, then your fish are likely to get stressed out, and may even die prematurely.

Think of your aquarium as a fish’s home – it needs to be spacious and clean as well as making them feel safe. You wouldn’t want to live in a cramped, poorly-lit apartment, would you? Fish, too, need to be kept in an environment they are happy and content in

With that in mind, here’s what to consider:

1. Determine What Fish You Want to Keep

Before you even start looking at aquariums, research the types of fish you’re interested in keeping. Different fish species have different needs in terms of space, water conditions, and tank setup. For example, some fish prefer a tall tank to a wide one and vice versa.

If you’re just getting started, then here’s a helpful article on the 15 Easiest Fish To Take Care Of! Over 150 people were polled for the results!

2. Consider the Size of the Aquarium

Once you know what kind of fish you want, you’ll have a better idea of the size of the tank you need. Generally, bigger is better as it provides more room for the fish and is easier to maintain stable water conditions. Remember, the rule of thumb is one gallon of water per inch of fish, but this may vary depending on the species.

3. Think About Location

Before purchasing your aquarium, decide where you’ll place it in your home. You’ll want a location that’s away from direct sunlight (to prevent algae growth), not too close to heating or air conditioning vents, and somewhere it can be easily seen and enjoyed. Make sure the floor is sturdy enough to hold the weight of the aquarium when it’s full of water.

4. Choose the Material

Fish tanks are usually made of glass or acrylic. Glass is cheaper, scratch-resistant, and less likely to discolor over time, but it’s also heavier and more prone to cracking. Acrylic tanks are lighter and more resistant to impact, but they can scratch easily.

5. Budget Considerations

Consider your budget. Remember that in addition to the tank, you’ll need to purchase equipment such as a heater, filter, lighting, substrate, and decorations. Plus, there are ongoing costs for food, water conditioners, and potentially medication.

6. Check the Condition

If you’re buying a new tank, this isn’t a concern, but if you’re getting a used one, inspect it thoroughly. Check for any scratches or cracks, and make sure the seals are intact.

7. Think About Aesthetics

Last but not least, choose an aquarium that you find visually appealing. This will become a centerpiece in your room, so choose a style that complements your interior design.

Choosing the right aquarium is a critical first step in your fishkeeping journey. Take your time and choose wisely. Your fish – and you – will be much happier for it.

What Do You Need To Setup Your Aquarium

Before you setup your aquarium, there are a lot of things you’re going to need to get started! Here’s a breakdown of everything you need!

The Tank Itself

First of all, you’re going to need the tank itself, if you’re just starting out, it’s probably easiest to use an aquarium kit. They often come in 5, 10 and 20 gallons. Aquarium kits also tend to be the cheaper than getting all the parts separately too!

20 gallons is going to be best for beginners because the more water there is, the less factors like temperature fluctuations or waste building up will affect the water itself.

With that being said, I started with a 10 gallon tank and never had any problems!

Tetra Aquarium, 20 Gallon, Complete Tropical Fish Tank Kit With LED Lighting And Decor For Freshwater Fish
  • GLASS AQUARIUM KIT: The kit includes one glass aquarium with a low-profile, hinged hood, an LED lighting system, an internal filter and filter cartridge, an aquarium heater and thermometer, a water conditioner sample
  • LED LIGHTING: Energy-efficient LEDs give you a beautiful natural daylight effect.
  • FILTRATION SYSTEM: The included Tetra Internal Filtration System features mechanical filtration to catch debris and chemical filtration with Ultra-Activated Carbon for removal of odors, discoloration and toxins.

Stand or Cabinet (Optional)

While it’s optional, aquarium cabinets are also something worth considering. I love them because they give you more storage space for all your equipment, and allow you to place your tank in areas of your house you may not have been able to before!

Ollie & Hutch Farmington 10/20 Gallon Aquarium Stand, Ivory
  • Get an aquarium stand that fits your needs with the Ollie & Hutch Farmington 10/20 Gallon Aquarium Stand
  • Made of laminated MDF and particleboard, the weathered off-white finish gives the Stand a rustic look
  • The Stand can support aquariums between 10 and 20 gallons and features an open back to make attaching tank accessories simple. Tank is not included


Filters are vital for maintaining water quality by removing waste and harmful chemicals. The size and type of filter needed will depend on the size of your tank and the species of fish you plan to keep.

When choosing filters there are a whole range of different ones to choose from. What’s more important is that they have the three stages of filtration every fish tank needs.

Mechanical filtration which removes large debris and waste, chemical filtration which removes bad odors and keeps the water crystal clear, and biological filtration where the beneficial bacteria in your tank is housed.

Beneficial bacteria is key for removing harmful chemicals like ammonia from the tank (you’ll learn more about the nitrogen cycle further down).

One thing to note is that oftentimes small filters will have a filter cartridge, that just needs replacing, instead of the individual media which is much easiest for beginners.

Tetra Whisper IQ Power Filter 20 Gallons, 130 GPH, with Stay Clean Technology
  • QUIET AQUARIUM FILTER: The Tetra Whisper IQ Power Filter with Stay Clean technology contains a sound shield for quiet filtration less than 40 dB.
  • SELF PRIMING: Submerged motor starts up with no priming required.
  • CAPACITY: The Tetra Whisper IQ 20 Power Filter works in filters up to 20 gallons (130 GPH).


If you’re going to be keeping tropical fish, it’s paramount that you also add a filter to your tank. Even if you live somewhere the weather is always warm, it only takes a strong draft or one cold day to drastically drop the temperature in the tank, which could prove fatal to your fish.

Generally speaking you can keep most tropical fish between the temperatures of 75-80°F, however, each fish will have their own individual needs.

Fluval M 100 Watt Submersible Heater
  • Submersible heater provides exceptional performance and unsurpassed reliability
  • The heater also includes an exclusive mirror technology that reflects the colours of the aquarium and enhances overall aesthetics
  • Sleek and compact


While your heater should be fine on it’s own, a thermometer will allow you to always know that it’s working fine. Afterall, if the heater become faulty, how else would you know.

When placing your thermometer, place it on the opposite end of the tank, so you can make sure the water across the whole tank is staying warm enough too.

AQUANEAT Aquarium Thermometer, Reptile Thermometer, Fish Tank Thermometer, Digital Thermometer, Terrarium Water Temperature Test, with Large LCD Display (1 Pack)
  • Wide application: Ideal for use in water or high moisture environment like aquarium terrarium, or vivarium; suitable for different water types such as fresh water, tap water, salty water, marine water and etc.
  • Easy to read: Comes with a large LCD display that is easy to read clearly
  • Easy to setup: Submerge probe with suction cup can easily be set in water (Submerge probe only, do not submerge thermometer in water) ; Press ”PWR” for 3 seconds to power off


If you’re going to be keeping plants in your tank (which I highly recommend), then aquarium lights are going to be essential! As well as this, they also help your fish establish a night time and daytime routine which is vital for their health!

Generally speaking fish need a light without about 5000 kelvin, but if you have a planted tank, you’ll need a tank with 6000-8000 kelvin.

If you really want to be safe, you can also get a timer for your lights so you don’t have to worry about forgetting to switch them on or off.

AQUANEAT LED Aquarium Light Full Spectrum for 18 Inch to 24 Inch Fish Tank Light Fresh Water Light Multi-Color
  • Fits aquarium tank up to 10 gal from 18″ to 24″ in length with adjustable mounting brackets
  • Light body without docking brackets: 17” L x 2.7” W. Tank thickness: No limit to rim size
  • Configuration: Total 42 LEDs, 30 pcs 6500K white LED, 6pcs blue LED, 3 pcs pink LED, 3 pcs Green LED

Air Pump/Air Stone (Optional)

While it’s not common for the water in your tank not to have enough oxygen, it does happen in tanks that are overcrowded. Fortunately, adding an air pump is a quick way to remedy this!

You can also use the current of your filter’s output to agitate the water, and add live plants too!

Pawfly Aquarium 4 Inch Air Stone, Fish Tank Airstone Bubble Diffuser for Air Pumps Buckets Fish Tanks Ponds DWC Reservoirs and Circulation
  • Medium Bubbles: The air stone can produces abundant dense bubbles to aerate your water reservoirs. A great way to increase oxygen solubility in your aquarium and enliven the aquatic lives.
  • Model: ASD100; Jetting volume: 12 L/min; Recommended air pump power: > 4 W; Inner diameter of tubing: 3/16″ or 3/8″. Great for aquariums, DWC systems or ponds. (Fit Tanks of 10-60 Gal)
  • Reliable Material: Made of mineral material and sintered at a high temperature, it causes no effect to the health of your aquatics. Keep fish or roots growing healthily.


The substrate is another important factor to consider when you’re setting your tank up. There are three main types you’re going to choose from, each with their own pros and cons.

Sand, Gravel, Or Aquarium Soil?

When choosing aquarium substrate, you’re going to be faced with three main options. Sand, gravel, or aquarium soil.


  • Advantages: Sand is an excellent choice for bottom-dwelling fish or species that like to sift through the substrate. It provides a smooth surface that’s gentle on sensitive bellies, and won’t damage barbels. Certain types of sand can also help maintain a more neutral pH level in your tank.
  • Disadvantages: Food and waste can often sit on the top of sand, making the tank appear dirty. It’s also a bit more challenging to clean as your gravel vacuum can often suck it up.
Aqua Natural Sugar White Sand 10lb Substrate for aquascaping, Aquariums, vivariums and terrariums
  • Triple washed and kiln dried – this is one of the cleanest aquarium sands available, no toxins, no foreign matter, 100% natural sand
  • 0.5 – 1mm in size – it has a dense composition and zero fines so does not blow around in your tank
  • Ethically and sustainably sourced under license in New Zealand


  • Advantages: Gravel comes in various sizes and colors, giving you more aesthetic options. It allows waste to fall between the gaps, keeping the surface clean, and helping beneficial bacteria grow in the small gaps. On top of this, gravel is also easy to clean with a standard aquarium vacuum.
  • Disadvantages: Fish that like to dig and forage may hurt themselves when they’re trying to forage through gravel. Certain types of gravel such as those that are limestone will alter the pH level of your tank.
Miukada 5 Pounds River Rocks, Pebbles, Decorative Polished Gravel, Natural Polished Mixed Color Stones
  • Miukada pebbles set are naturally polished for smooth effect, and come in a variety of natural colors and patterns. There are popular natural color and shades on them such as brown, white, black, red, grey.
  • Please kindly understand that rocks are natural so some of them may be broken or out of shape, oval or round, thick or thin. However, we add a little more rocks in each package to ensure our customer can get enough high quality rocks.
  • These river rocks can add an extra beauty in your garden or just outside your house and be a perfect home décor, a creative interior or exterior design.

Aquarium Soil:

  • Advantages: Aquarium soil, is specially designed for tanks with live plants. It contains nutrients that help plants grow and typically helps maintain a lower pH, which is beneficial for many freshwater fish and plants.
  • Disadvantages: Aquarium soil can be more expensive than sand or gravel. It also tends to cloud the water when initially set up, and if disturbed (by burrowing fish, for example), it can make the water murky.
Fluval 12693 Plant and Shrimp Stratum for Freshwater Fish Tanks, 4.4 lbs. – Aquarium Substrate for Strong Plant Growth, Supports Neutral to Slightly Acidic pH
  • Facilitates Rapid and Beneficial Colonization: Its porous structure enables swift colonization of beneficial nitrifying organisms, fostering a healthy aquatic environment crucial for the well-being of aquarium inhabitants
  • Maintains Optimal pH Levels: Designed to sustain a neutral to slightly acidic pH range, ideal for supporting the growth of various plants, tropical fish, and shrimp commonly found in planted aquarium setups
  • Offers Shelter for Newborn Shrimp: Stratum provides a safe haven for newborn shrimp, offering protection from potential predators until they reach a size where emerging into the main aquarium is viable

I personally would opt for Aquarium Soil. I think it’s always a good idea to have live plants in your tank, especially when you’re just getting started as they’re going to help keep the tank clean, as well as oxygenate the water.

Aquarium Decorations, Ornaments, and Plants

Plants and decorations aren’t just there to make your tank look more aesthetic. They actually serve a much more important job. They’re going to give your fish plenty of places to hide. Which is vital if you plan on keeping multiple fish together!

Places to hide will give them spots where they can relax and feel safe away from other fish.

When you’re picking decorations, try to think of things like driftwood, caves, and rocks where your fish go to be alone.

Water Conditioner

Water conditioner is used to make sure all the chlorine, chloramines and heavy metals are removed from the water before it’s added to the tank. Without this your fish can literally die within minutes.

I personally like to use API Stress Coat. Not only is it a water conditioner, but it also has aloe vera added to it which helps reduce stress in fish and improve their slime coat! (The coating on their skin, that helps keep infections out).

API STRESS COAT Aquarium Water Conditioner 16-Ounce Bottle
  • Contains one (1) API STRESS COAT Aquarium Water Conditioner 16-Ounce Bottle
  • Makes tap water safe and protects fish with dual-action formula
  • Removes chemicals from tap water that are harmful to fish

Aquarium Test Kit

When you’re cycling your tank (or when it’s established) you’ll need an aquarium test kit to check the ammonia, nitrite, and nitrate levels to make sure they’re all at the right levels.

As well as this you can also use your water testing kit to check the pH and make sure that it’s the right level for your fish.

API FRESHWATER MASTER TEST KIT 800-Test Freshwater Aquarium Water Master Test Kit, White, Single, Multi-colored
  • Contains one (1) API FRESHWATER MASTER TEST KIT 800-Test Freshwater Aquarium Water Master Test Kit, including 7 bottles of testing solutions, 1 color card and 4 tubes with cap
  • Helps monitor water quality and prevent invisible water problems that can be harmful to fish and cause fish loss
  • Accurately monitors 5 most vital water parameters levels in freshwater aquariums: pH, high range pH, ammonia, nitrite, nitrate

Biological Starter

Again, whilst not essential, biological starter is going to help your tank cycle even faster. It introduces beneficial bacteria into the tank, so you don’t have to wait for it to grow naturally when you add a source of decay.

Fluval Cycle Biological Enhancer, Aquarium Water Treatment, 8.4 Oz., A8349
  • All-natural water care creates a safe biological habitat to prevent fish loss by eliminating ammonia and nitrite
  • Infused with a powerful team of beneficial bacteria that immediately inoculates aquarium water
  • Extremely effective when setting up a new aquarium or introducing new fish to an existing one and useful during water changes and filter media changes, when good bacteria is depleted

Fish Net

A net isn’t completely essential, however, that do make things a lot easier. They can help you scoop fish up when you need to transfer them. Or if like me you end up with some greedy fish, it can allow you to scoop them up while you feed your other fish!

Marina 3-Inch Blue Fine Nylon Net with 10-Inch Handle, Aquarium Maintenance Tool, Blue, 11273
  • Made with high quality materials; the soft nylon woven mesh material is perfect for gently scooping fish
  • Allows for easy fish tank maintenance
  • Great to use in either a freshwater fish tank or a salt water fishtank


And of course, you’re going to need make sure you have food for your fish! Always check the diet requirements of your fish. Most are omnivores, however, some will be herbivores, and other’s carnivores.

On top of this, you may also have bottom feeders that have a much easier time eating from the substrate, or fish with upturned mouths which can only eat from the surface of the water!

Always research your specific fish’s needs first!

TetraMin Plus Tropical Flakes, Cleaner and Clearer Water Formula 7.06 Ounce (Pack of 1)
  • TROPICAL FORMULATION: Highly digestible flake blend for use as staple food for all tropical fish.
  • PLUS SHRIMP: With natural shrimp for maximum flavor – a natural attractant for aquarium fish.
  • FOR ALL TROPICAL FISH: ProCare blend helps support your fish’s immune system for optimal health and long life.

A Gravel Vacuum

When you’re cleaning your fish tank, a gravel vacuum is essential. Not only is it a great way to remove water from the tank, but it also helps remove waste build-up from the substrate itself!

Laifoo 5ft Aquarium Siphon Vacuum Cleaner for Fish Tank Cleaning Gravel & Sand
  • FUNCTION — Easy to control, convenient to siphon fish faeces, impurities, turbid water out of fish tank.
  • 5 Feet HOSE — Made from clear & elastic plastic. Makes it more durable and anti-kinking. Harmless to fishes & No peculiar smell.
  • GRAVEL TUBE — Sinkable, with a detachable filter screen inside. Will not disturb fish or decor when it’s working.

Algae Scrubber (Optional)

While you don’t need an algae scrubber, I’d definitely recommend one. Algae is going to grow on the glass of your tank whether you want it to or not. So unless you don’t want to see your fish, you’ll need to invest in an algae scrubber to remove it!

I personally like a 5 in 1 kit as the scraper can be a lot more effective than a scrubber in a lot of circumstances!

hygger Small Fish Tank Cleaner, Aquarium Cleaning Tools Kit with Handle, Seaweed Scraper, Fishing Net, Sponge Brush,Wall Brush (M)
  • 🐠【Design concept】It is specially designed for the small mini fish tank, no longer need to be embarrassed by the inconvenience of using large cleaning tools, the uncleanness of using hands, and the inability to reach into the fish tank. This small aquarium cleaning tool can be fully used by children, not bulky, light and convenient.
  • 🐠【Multifunctional 4 in 1】Aquarium cleaning kit includes 1 handle, 1 scraper, 1 small fishing net, 1 right angle sponge brush, 1 wall brush. hygger small fish tank cleaner kit can do a basic fish tank cleaning job. It is an indispensable tool for all small aquariums.
  • 🐠【Function head introduction 1】Flat cleaning brush, high-density filter cotton, good adsorption, strong cleaning power, not easy to deform. Scraper, efficiently clean fish tank and remove stubborn stains.

(Side Note: It’s normally best to have a bucket for your water changes, but I assume you already have one somewhere at home.)

How To Setup Your Fish Tank

Now you know everything about what to buy! You need to know how to put it altogether to create the perfect tank for your new fish!

  1. Finding the Perfect Spot for Your Aquarium

First things first, you’ve got to decide on the size and type of your aquarium. Once that’s sorted, it’s all about location, location, location!

As a rule of thumb there are a few things to remember when picking the ideal spot for your aquarium.

  • Keep It Away From Direct Sunlight – Direct sunlight will cause algae growth to rocket in your tank, and on top of this it could potentially heat the tank up too much.
  • Avoid Drafts & Cold Spots – You should also make sure you’re avoiding drafts and cold spots, especially with smaller tanks. Both can drop the temperature in the tank which can kill your fish.
  • Avoid Noisy Areas – It’s also a good idea to avoid putting your fish tank in noisy areas. Noisy areas will stress your fish out, so it’s best to keep it somewhere peaceful and tranquil.
  • Out Of Reach Of Pets & Children – Lastly, you should also keep the tank out of reach of pets and small children. It only takes a bit of curiosity and you could end up with some dead fish.
  1. Laying the Groundwork with Substrate

Think of substrate like the carpet in your home—it covers the bottom of your tank. Whether you choose gravel, sand, or aquarium soil, make sure to rinse it thoroughly to get rid of any dust. Then, lay it in your tank at a depth of about 2 inches.

  1. Setting Up Your Equipment

Now it’s time to install your heater, filter, thermometer, and maybe an air pump if you’ve got one. It’s important you don’t turn them on at this point. They need water to function properly. and if you turn them on without the water in the tank, they may end up breaking.

  1. Bringing Your Tank to Life with Decorations and Plants

Time to make your fish feel at home with some decorations and plants. Rinse them in warm water first to remove any dust etc, then place them in your aquarium. Remember, you should provide plenty of hiding spots for your fish, but still leave enough room for them to swim freely.

  1. Filling Your Tank with Water

Next up, fill your tank with dechlorinated tap water. To dechlorinate your water, you’ll need water conditioner. And remember to fill it slowly—you don’t want to disturb your carefully arranged substrate and decorations.

I find that placing a place into the tank, or holding it over where you’re pouring water is the best way to leave everything is undisturbed as possible.

  1. Getting Your Equipment Up and Running

Once your tank is filled, you’re good to go ahead and start your filter, heater, and any other equipment. Double-check that everything is working as it should.

  1. Cycling Your Tank: Patience is Key!

You may be thinking now you can just add your fish! Unfortunately not.

Before you introduce your fish, you need to cycle your new aquarium! This helps to establish the beneficial bacteria that will help maintain water quality. It can take a few weeks, but your fish will thank you for it!

(You’ll find out how to cycle your tank further into this article)

  1. Testing the Waters

Once your tank has cycled, it’s time to test the tanks water parameters like pH, ammonia, nitrites, and nitrates. Once your sure everything is in order, it’s time for the final step!

  1. Welcoming Your Fish to Their New Home

Finally, the moment you’ve been waiting for—adding your fish to the tank! Make sure to acclimate them to the water temperature first by floating their transport bag in the tank for about 15 minutes. Then, gently net the fish from the bag and release them into their new aquatic kingdom.


To make setting up your tank easier, here’s a handy checklist for what you need to do!

Tank setup checklist

The Nitrogen Cycle (In Short)

Even though you’ve setup your fish tank, it’s not over yet. You need to cycle the tank before you can add fish. And to cycle the tank you need to know about the nitrogen cycle! Imagine the nitrogen cycle as nature’s own waste management system, specifically for bodies of water. Here’s how it works:

  1. Ammonia: Fish waste, leftover food, and decaying plant matter all produce ammonia. Now, ammonia is like the stale, smelly garbage in this analogy. And just like that garbage, too much ammonia is harmful, even deadly, to fish.
  2. Nitrites: This is where the good bacteria, nitrosomonas, come in. They’re like the garbage collectors of the tank, converting that nasty ammonia into nitrites. But hold up, nitrites are still toxic to fish—it’s like trading garbage for toxic waste.
  3. Nitrates: Next up, another set of good bacteria, nitrobacter, convert nitrites into nitrates. This is a bit like turning that toxic waste into compost. Nitrates are much less harmful to fish, but they can still cause issues in high amounts.
  4. Plant Utilization and Water Changes: Here’s the final step. Live plants in your aquarium can absorb some of these nitrates as food, turning our ‘compost’ into a helpful nutrient. Regular water changes also help by physically removing some of the nitrates from your tank.

So, in essence, the nitrogen cycle turns harmful waste into a less harmful substance that can be managed with proper tank maintenance.

Here’s a handy diagram to help you understand easier!

The Nitrogen Cycle

Cycling Your Tank

There are two main ways to cycle your fish tank, you can either do a fishless cycle or fish in cycle. Fish-in cycles are a lot more harmful to your fish and definitely not recommended.

Fish-In Cycle

The fish-in cycle involves adding hardy, waste-producing fish to a new tank. As the fish produce waste, they provide a source of ammonia, which kicks off the nitrogen cycle.

However, this method has been somewhat controversial because it exposes the fish to potentially harmful levels of ammonia and nitrites before the cycle is fully established. If you choose this method, it’s important to closely monitor water parameters and do frequent water changes to help keep toxin levels low.

Ideal fish for this method are hardy species like zebra danios or certain types of guppies that can tolerate the changing conditions better than most.

Fishless Cycle

The fishless cycle is often considered a more humane method because it doesn’t expose fish to harmful ammonia and nitrite levels. Instead, you add an ammonia source (like fish food or pure ammonia) to the tank to start the cycle.

This method requires patience, as you have to wait for ammonia and nitrite levels to spike and then fall back to zero before it’s safe to add fish. This can take several weeks, but it’s worth it to provide a safe environment for your fish from the get-go.

Using a bacterial starter culture can help speed up this process. These are commercially available products containing strains of the beneficial bacteria that you’re trying to establish in your tank. By adding a starter culture, you’re effectively giving your cycle a head start.

No matter which method you choose, remember that cycling your tank is a crucial step in setting up a healthy aquarium. It’s all about creating the best home possible for your aquatic friends!

Fish In Vs Fishless Cycle

Click Here For A Complete Guide The Nitrogen Cycle And How To Cycle Your Aquarium

How Long Should You Wait Before Adding Fish To Your Tank?

You should wait until the ammonia and nitrite levels are at 0ppm and the ammonia levels are at 20ppm before adding new fish to your tank. In my experience this is between 4-6 weeks after cycling has started normally.

A Quick Note On pH & Temperature

When it comes to setting up a fish tank, the pH and temperature are essential factors that depend on the specific fish you’re keeping. Now, don’t worry, it’s not as complicated as it sounds.


Let’s start with pH. Most freshwater fish prefer a pH range of 6.5 to 7.5, which means slightly acidic to slightly alkaline conditions. But of course, some fish that may have different preferences.

Some may like it a bit more acidic, while others might prefer things on the alkaline side. It’s crucial to know the preferred pH range of the fish you’re choosing beforehand to make sure they’re the right fit for your aquarium or too adjust the tank accordingly.


Next up is the temperature. Fish are cold blooded, so getting the temperature right is essential. Most tropical fish like a temperature range of 75°F to 80°F (24°C to 27°C). (As you can guess these are the temperature they’re often found in.)

But remember, there are exceptions. Some fish may be more comfortable in cooler waters, while others might prefer it a bit warmer. So, it’s important to do your research and find out the specific temperature requirements before you purchase your fish.

Caution About pH And Temperature

One more thing to note. Sudden changes in pH or temperature can stress out fish, and nobody wants that. In fact, when sudden changes in pH or temperature occur it can cause your fish to go into shock, which can be fatal in some circumstances.

Common Mistakes People Make

  1. Choosing a small aquarium: Small tanks can lead to unstable water conditions and limited space for fish. So make sure you’re using a large enough tank for better stability and more room for your fish to swim.
  2. Adding fish before the aquarium is ready: Wait until your tank has stable water parameters and completes the nitrogen cycle before introducing fish. If you don’t exercise patience now your fish will end up suffering.
  3. Not routinely testing the water: Regularly check pH levels, ammonia, nitrites, nitrates, and water hardness to monitor and maintain optimal water quality for your fish.
  4. Insufficient water changes: Regular water changes are essential for removing waste and maintaining clean water. Aim for a 10-15% water change each once or twice a week to keep your fish happy and healthy.
  5. Overfeeding: It’s best to only feed your fish what they can eat in 1-2 minutes 2-3 times a day. However, some fish (like algae eaters) may require even less than this.
  6. Adding too many fish at once: You should gradually introduce fish to your tank to allow the nitrogen cycle and to stop ammonia spikes. If you have a small tank I wouldn’t add more than 2 small fish, but if it’s bigger you may be able to add 3-4.
  7. Keeping too many fish: Overstocking your tank is going to increase the risk of ammonia spikes, and oxygen deprivation in the tank, as well as compromising the water quality in general.
  8. Blindly trusting pet stores: While some pet stores offer reliable advice, it’s essential to do your research and seek information from reputable sources to make informed decisions about fishkeeping. Remember, fish stores are trying to sell at the end of the day.
  9. Not using live plants: Live plants are amazing for your tank because they oxygenate it, provides natural filtration, and reduces algae growth by consuming the nutrients algae needs. Consider adding live plants to enhance the health and aesthetics of your aquarium.
  10. Using cheap equipment: If you use cheap equipment your fish are going to suffer for it. A good filter is the most important. Poor water quality in the tank is the first thing that will cause your fish to suffer. And as well as this, you should also invest in a high quality heater. A heater that breaks could prove catastrophic for your fish.
  11. Accidental poisoning: Oftentimes, people spray things such as deodorant around the tank, or put their hand in the water when there’s still soap or other detergents on them. This can be fatal to fish, especially smaller fish
  12. Mixing incompatible fish: Some fish can’t be kept for a number of reasons including, aggression or just different water parameters. If you try and keep the wrong fish together, one or both types may die.
  13. Constantly rearranging the aquarium: Frequent changes can stress your fish. Set up your tank with a suitable layout from the start and avoid unnecessary disruptions, remember, you want the tank to be as undisturbed as possible.
  14. Not treating algae appropriately: When you see algae in your tank you should get rid of it as fast as possible. The longer you leave it the worst it will get. Sometimes, it will even grow on your plants stopping them from getting the nutrients they need.
  15. Using too many chemicals: Excessive use of chemicals can disrupt the balance of your tank and eventually harm your fish. So you should only use chemicals when they’re absolutely necessary.
  16. No maintenance schedule: Establishing a regular maintenance routine for your tank, is key for the ongoing health of your fish. So make sure to make a schedule for water changes, filter cleaning, and testing water parameters
  17. Not acclimating new fish properly: When introducing new fish to your tank, it’s important to acclimate them slowly to minimize stress and allow them to adjust to the water conditions.
  18. Neglecting to quarantine new fish: Quarantining new fish before adding them to your main tank helps prevent the spread of diseases and parasites into your existing fish tank.
  19. Neglecting to clean aquarium equipment: Regularly clean your aquarium equipment, including filters, heaters, and air pumps, to prevent the build-up of debris and maintain their efficiency. Also make sure that you’re disinfecting any aquarium equipment that has come into contact with sick fish or water.
  20. Overlooking the importance of water circulation: Proper water circulation helps distribute heat, oxygen, and nutrients evenly throughout the tank. Without this your fish may end up suffering or staying in certain areas of the tank.
  21. Not providing adequate hiding spots: Fish need hiding spots to feel secure and reduce stress. Include caves, plants, and other structures in your tank to provide hiding places for your fish. Paradoxically, the more hiding spaces there are in your tank, the more confident your fish will feel, and the more likely they are to stay in open spaces.
  22. Neglecting to address aggressive behavior: If you observe aggressive behavior among your fish, take action to prevent injuries and death. Separating aggressive fish or providing more hiding spots can help reduce aggression.
  23. Buying Sick/Weak Fish: A lot of times people will buy fish that are sick or weak by accident. For example, you should never buy betta fish from cups, as they will most likely be extremely unhealthy. Also by buying bettas like this, you’re encouraging fish stores to keep them in these conditions.
  24. Failing to provide a balanced diet: Feed your fish a varied and balanced diet to ensure they receive the necessary nutrients. Remember, fish flakes, pellets, wafers etc should be the staple of their diet, but make sure you’re also supplementing this with live, frozen, and freeze dried food as well as plant matter depending on the fish you have.
Mistakes Setting Up A Fish Tank

Acclimating Your Fish

When introducing new fish to your aquarium, it’s crucial to acclimate them properly. Acclimation is the process of adjusting them to the new water parameters. Without this adjustment, your fish will become a lot more stressed. More sensitive fish may even die.

Float The Bag

When you get your fish, you’re going to transport them home in a bag on most occasions. So when you get home, gently float the bag in your fish in the tank for about 15 to 20 minutes. This gives the fish time to get used to the temperature in the tank.

On top of this, if your housing other fish in the tank, it’s going to give you an insight in how they’ll react to each other. If you notice aggression, then you may need to consider housing your fish elsewhere.

Add Tank Water To The Bag

After the floating period, add a small amount of tank water into the bag every few minutes for about 20 to 30 minutes. This helps the fish adjust to the pH and other water conditions in your tank.

Transfer Your Fish

Once the acclimation period is over, carefully release your fish into their new home. You should use a net to transfer them from the bag to the tank.

You want as little of the water from the bag to go into the tank as possible. I’ve known so many people who have introduced parasites and bacteria into their tank by dumping the bags water in. Especially in cases where you haven’t brought your fish from a reputable store.

A Quick Tip

Now your fish is in the tank, it’s a good idea to keep the lights dim and ensure there are lots of hiding places for them. This way they’ll feel less stressed and a lot more protected.

Keep An Eye On Them

After releasing the fish, keep an eye on them for a while to ensure they’re swimming comfortably and behaving normally. It’s normal for fish to take some time to explore their surroundings and get used to the new environment. Give them space and let them settle in at their own pace.

Remember, acclimating your fish is important to help them transition smoothly. It reduces the risk of shock and stress, increasing their chances of thriving in their new aquatic home. So take your time, be patient, and let your fish find their fins in their new home.

Maintaining Your Fish Tank

Daily Maintenance: Every day, it’s a good idea to give your aquarium a quick check-up. Take a moment to look at the tank and make sure everything is running smoothly. Are the filter and lights doing their job, keeping the water clean and well-lit?

Check the temperature to ensure it’s just right too. Count your fish and observe their behavior, if you notice fish hiding, or one is missing, there could be a bully in the tank!

And after feeding them, keep an eye out for any leftover food. If there’s too much, remove some, and consider whether it’s time to adjust their portions. Also if the water level seems a bit low, simply top it off with some treated or aged water.

Starting an aquarium journal or logbook can be a fun way to keep track of any interesting observations during your daily checks. You don’t need to write a novel—just jot down anything unusual or noteworthy. Overtime you may begin to notice subtle changes in your fish that could show a problem.

Weekly/Bi-Weekly Maintenance: Now, let’s talk about the regular cleaning routine. Every week or every other week, it’s time to give your aquarium some TLC. Start by grabbing your algae scraper and giving the inside of the glass a good scrape to remove any stubborn algae.

Take a short break and let everything settle down for a few minutes. Then grab your siphon and carefully clean the substrate to get rid of any lingering debris, hover the vacuum above the substrate, so you don’t end up sucking that up.

During the wait time can be a great time to check the water parameters. Use your test kit to test for ammonia, nitrite, nitrates and pH and make sure everything is in order.

Finally, it’s time for a partial water change, this should be done at the end of the cleaning, so you don’t can remove any excess debris floating around in the water.

Monthly Maintenance:

During the monthly maintenance is the time where you’ll generally need to trim your plants a bit. So that should be one of the first things you do.

During the fourth week of water changes, make sure you don’t chuck the aquarium water out straight away. Instead rinse the mechanical filter media in the saved water, (after a few months, no matter how much you wash it, it will be so dirty you’ll just need to replace it).

But remember, don’t replace all the filter media at once—keep a portion to preserve as much beneficial bacteria as possible. You can replace the remaining media next month.

While the mechanical filter may need replacing every few months, your chemical filter media should be replaced every couple of weeks in most cases. And lastly, you should try to keep the biological media in your tank as long as possible.

Periodic Maintenance: Apart from the regular tasks, there are a few things you need to do as needed. For example, the light bulbs are going to give out at some point, so they’ll need changing.

Also check the air pump tubing and filter tubing periodically to make sure there are no blockages or damage. You may need to use a pipe scrubber to get into these tubes and remove any buildup.

If you’re not using aquarium soil in your tank, then you may need to add fertilizer. Generally if your plants are starting to turn yellow, it’s a sign they need fertilization!

Trouble Shooting Problems

Here are some common aquarium problems and how you can fix them!

Cloudy Water– Bacterial bloom during the nitrogen cycle in new tanks.
– Overfeeding and excess fish food
– Monitor water parameters and give the tank time to establish a healthy balance. – – Adjust feeding amounts and remove uneaten food
Aquarium Odor-Overfeeding,
-Accumulation of fish waste and sludge in gravel
– Reduce feeding amounts and frequency. – Clean gravel monthly using a siphon.
– Use activated carbon (chemical filter media) to eliminate odors
Fuzzy White Patches– Overfeeding and excess fish food create white mold– Remove all the white patches when you see them
– Reduce overfeeding
– Clean tank more frequently.
Algae on Glass and Gravel– Excessive nutrients in the water.
– Extended light exposure
– Do weekly water changes to dilute nutrients
– Scrape off algae promptly from glass
– Add more live plants to your tank
-Leave the lights off for longer
Green Water– Excessive algae growth due to high nutrients and light. – Algae imbalance– Turn off lights
– Perform partial water changes
– Consider using algaecides temporarily to restore balance
Mineral Build-Up– Water splashing and evaporation causing mineral deposits– Minimize water splashing
– Clean decorations with vinegar, thoroughly remove the vinegar and add the decoration back to the tank.
Snails– Snails and snail eggs entering with live plants– Inspect and quarantine plants before adding to the tank
– Use snail traps
– Introduce loaches to control snail populations
Discolored Water– Bacterial Bloom
– High fish population
– Heavy feeding
– Tannins
– Perform weekly water changes
– Use fresh activated carbon or change filter media
– Boil driftwood for longer
– Consider removing Indian Almond Leaves
Sick Fish– Poor water quality (high ammonia or nitrite levels)
– Incorrect water temperature
– Test water parameters regularly and ensure it’s good
-Make sure the tank is the correct temperature.
pH Level Problems– Fluctuations outside the acceptable range– Test pH monthly and adjust if necessary using aquarium-safe products

That’s pretty much EVERYTHING you need to know on setting up your fish tank, avoiding mistakes, and troubleshooting any problems you come into

But you may still be scratching your head about what to add to your tank! Here are some of the best plants and fish I’d recommend for beginners!

Top 10 Aquarium Plants

Marimo Moss Balls: These unique green orbs, actually made from algae are the easiest plants to care for in your tank. Just roll them lightly during water changes to maintain their shape and ensure all parts receive light. They’re great for betta tanks or goldfish aquariums. In fact, you may even notice more curious fish rolling them.

Amazon Sword: Known for it’s lush green leaves and large growth, Amazon sword is a great background plant for tabs. Feed Amazon Sword root tabs to keep it healthy, and don’t worry if the initial emersed-grown leaves melt back—new submersed-grown leaves will appear.

3 Amazon Sword Aquarium Plant Live | Echinodorus Bleheri
  • Easy live aquarium plant specie for any freshwater aquarium
  • Create a natural habitat in your aquarium for your fish and invertebrates
  • Make your fish tank look natural and beautiful

Cryptocoryne Wendtii: This low-maintenance crypt doesn’t need liquid fertilizers or CO2 injection. It thrives in various lighting and substrate conditions, but adding root tabs every few months can help for optimal growth. Unlike other plants on this list, Cryptocoryne Wendtii is red! And you can enhance the redness of its leaves by dosing extra iron supplements.

Aponogetons: A bulb plant that produces long, wavy-edged leaves, Aponogetons are ideal for beginners looking for easy care and quick growth. During dormancy, the larger leaves may die back, but new growth will emerge. I use to keep these with my betta as they’re perfect for betta tanks (hence their other name betta bulbs).

Crispus (Aponogeton crispus) Bare Root Aquarium Plant
  • Vibrant and Healthy: Our Crispus is carefully grown and shipped as a bare root to ensure optimal health and coloration.
  • Easy to Plant: This aquatic plant is simple to plant and perfect for beginners or experienced aquarists.
  • Oxygenation: This plant produces oxygen and helps maintain a healthy aquarium environment.

Bacopa Caroliniana: If you’re interested in stem plants, Bacopa is a beginner-friendly option. It doesn’t require CO2 injection but it will however benefit from liquid fertilizers. When it grows to tall just cut off the tops and replant them to create a fuller look.

Bacopa (Bacopa Caroliniana) – BUY3GET1FREE – Live Aquarium Plant
  • Plants provide great shelter from smaller aquarium inhabitants including baby fish, and invertebrates.
  • All our plants are grown in the best environment possible with high output lights and injected CO2. As well as liquid fertilizers every week. You can expect a high quality plant that is algae and snail pest free.
  • SHIPPING ALWAYS COMBINED – Buy as many plants as you’d like for 1 combined low flat rate. Give it a try!

Java Moss: This is another one of my favourite plants, not just for beginners, but for everyone! Just tie it to something in your tank and let it grow. It’s best for people who want that overgrown look, but with proper pruning you can turn it into all sorts of shapes.

Moss for Aquariums | Live Aquatic Moss for Freshwater Aquariums (Java Moss)
  • Live Aquatic Moss for Freshwater Aquariums. You get 1 Moss portion in a 4 oz Cup
  • Moss can be tied or glued to wood, rocks or left as is. Give your aquarium a natural look
  • Gives small fish and invertebrates a place to hide

Christmas Moss: This slow-growing moss resembles little Christmas trees thanks to the way it’s branches overlap each other and it provides excellent cover for baby fish and shrimp. You’ll need to tie it to rocks or wood to keep it from floating around the tank.

Marcus Fish Tanks – 3X Christmas Moss Vesicularia Montagne Live Freshwater Aquarium Plants Xmas Moss
  • LIVE AQUARIUM PLANT – 3 Christmas Moss Vesicularia Montagnei
  • SIZE – 3 Christmas Moss (Vesicularia Montagnei) golf ball size portion or larger, we like to be generous. Size will vary slightly as these are live plants.
  • LIVE ARRIVAL GUARANTEE – We guarantee live arrival on all of our livestock. If a plant ever arrives dead send us a clear photo of the plant in the unopened bag within 24 hours of delivery and and we will replace once verified.

Vallisneria: Vallisneria is perfect for creating an underwater jungle effortlessly. With root tabs and liquid fertilizers, it can grow tall and spread through side shoots. When you get more experienced, you may notice that some fish like to disturb plants. However, Vallisneria can handle it!

Jungle Vallisneria Rooted Plants 15-20 inches Tall – Easy Background Aquarium Plants
  • PLEASE READ BEFORE ORDERING: Please note that during times of extreme weather conditions, live plants will suffer due to extreme temperatures. During winter, do not order live plants when temperatures are expected to go below 20F at the lowest point during the day. During summer, avoid ordering plants when temperatures are above 100F. If you place an order under extreme weather conditions we will not able to guarantee live arrival
  • You will receive a bunch of Jungle Vallisneria with at least 2 rhizomes. These plants come with their roots trimmed since they are inspected by USDA for bloodworms prior to being available for sale. However, the plants will root very fast once planted.
  • Easy live aquarium plant specie for any freshwater aquarium. Make your fish tank look natural and beautiful

Java Fern: Unlike Java Moss, Java Fern has long, pointed leaves with deeply ridged veins. (They both have the same name due to where they come from.) Attach it to rocks or wood, as its roots and leaves sprout from the rhizome. Liquid fertilizers nourish its roots, and it propagates through cuttings or floating leaves.

Java Fern Bare Root | Microsorum Pteropus – Low Light Freshwater Aquarium Plant
  • Provide natural resting and hiding places for your smaller fish and invertebrates
  • Make your fish tank look natural and beautiful; Perfect for aquariums of any size
  • This Java Fern s a great and easy way to attaching Java fern to driftwood, rocks, etc

Dwarf Sagittaria: This hardy, grass-like plant makes for an easy carpeting plant in your aquarium. It stays small with high light and spreads through runners (grows out of the base of the plant).

Dwarf Sagitaria – Easy Foreground Aquarium Cover Plant
  • IMPORTANT: Please note that during times of extreme weather, live plants will suffer due to extreme temperatures. During winter, do not order live plants when temperatures are expected to go below 20F at the lowest point during the day. During summer, avoid ordering plants when temperatures are above 100F.
  • You get 1 Dwarf Sagittaria Plant bunch. An easy aquarium plant specie for any freshwater aquarium
  • Create a natural habitat in your aquarium for your fish and invertebrates. Make your fish tank look natural and beautiful

Top 15 Fish For Beginners

What fish tank setup guide would be complete, without telling you some of the easiest fish you can keep! With that being said, here are some of the best choices for you!

Guppies: Colorful and lively, guppies are hardy and adaptable fish that come in a wide range of patterns and colors. They are forgiving of beginner mistakes, making them a great choice for newcomers to fishkeeping.

Zebra Danios: With their striking black and white stripes, zebra danios are energetic and peaceful fish. They can handle a range of water conditions, making them a great choice for beginners.

Platies: Friendly and sociable, platies are easy to care for and can adapt to different water conditions. Their vibrant colors and livebearing nature are the reason they’re such a great choice for anyone just getting into the hobby!

Mollies: Active and attractive, there is an unbelievable amount of variations when it comes to mollies. They’re hardy fish, making them a great choice.

Common/Bronze Corydoras: Corydoras catfish, or cory cats, are bottom-dwelling fish. While these are some of the easiest types to keep, there are plenty of different cory’s you can choose from when just getting started. And as peaceful bottom dwellers, they’re not going to bother the rest of your fish either!

Cardinal Tetras: Slightly bigger than neon tetras, cardinals are also great beginner fish. Just make sure that you’re keeping them in a 20 gallon tank or bigger as they live the extra swimming space.

White Cloud Mountain Minnows: White cloud mountain minnows are attractive and resilient fish who can tolerate a wide range of temperatures. They do better in cold water aquariums, however, it is possible to keep them in cooler tropical aquariums too (as long as you’re keeping the temperature cooler).

Swordtails: Swordtails are another type of colorful fish great for beginners. If you’re new to fish keeping, but you’re looking for a big fish they’re your best choice! Just make sure you’re keeping them in groups of 5-6

Kuhli Loaches: With their eel-like bodies and playful nature, kuhli loaches add a whole bunch character to the aquarium. However, they’re nocturnal and may hide during the day but bring excitement when they come out to explore and scavenge for food.

Dwarf Gouramis: Unlike other types of gouramis, dwarf gouramis aren’t aggressive, in fact they’re incredibly peaceful! Which means they’re going to be a great choice for any beginner. Just make sure you’re keeping them in groups of 3 or more.

Endler’s Livebearers: Endler’s livebearers are small, colorful fish closely related to guppies. They’re hardy, adaptable, and easy to breed, making them a delightful choice for beginners. In fact, if you keep Endler’s and guppies in the same tank they can even breed with each other.

Bristlenose Plecos: Bristlenose plecos are another great choice if you pick a tank that’s big enough. Make sure you’re tank is 30 gallons in size, and make sure that they’re getting plenty of plant matter in their diet.

Cherry Barbs: Unlike other barbs, cherry barbs are incredibly peaceful! On top of this, they’re also fairly hardy, making them great choices for beginners.

Harlequin Rasboras: These aren’t my favourite fish, however, they are great for beginners. If you’re looking for a hardy, reliable fish, then they’re a great choice.

Neon Tetras: Neon tetras are some of the most popular fish in the trade and for good reason! However, they’re only good for beginners when they’ve been added to established tanks. So if you do want them, make sure you’ve already added other fish to the tank first.

easiest fish to take care of

All of these fish are great choices for a community tank! In fact, if you’re curious here are over 50 community fish.

Common Diseases

Fish can suffer from a whole variety of diseases, and it’s important to note that specific diseases can vary depending on the species of fish. However, some of the most common diseases that affect fish in general include:

  1. Ich (Ichthyophthirius multifiliis): Ich is a common parasitic infection that appears as white spots on the fish’s body, fins, and gills. It causes itching, irritation, and can lead to secondary infections if left untreated.
  2. Fin Rot: Fin Rot is a bacterial infection that causes the deterioration of the fish’s fins, leading to fraying, discoloration, and sometimes complete loss of the fin tissue.
  3. Fungal Infections: Fungal infections can occur when fish have open wounds or damaged skin. They often appear as white or gray cotton-like growths on the body, fins, or mouth.
  4. Swim Bladder Disorder: Swim Bladder Disorder affects the swim bladder, an organ that helps fish control their buoyancy. It can cause the fish to float uncontrollably or sink to the bottom of the tank.
  5. Dropsy: Dropsy is a symptom of an underlying condition, usually related to kidney or liver failure. It causes the fish to swell up, exhibit bloating, and may result in protruding scales.
  6. Bacterial Infections: Bacterial infections can affect fish in various ways, leading to ulcers, sores, or other visible signs of infection. These infections can be caused by poor water quality, stress, or injuries.
  7. Velvet Disease (Oodinium): Velvet is a parasitic infection that appears as a golden or rust-colored dust on the fish’s body, resembling velvet. It can cause lethargy, loss of appetite, and rapid breathing.

Proper aquarium maintenance, including regular water changes, keeping the correct water parameters, and providing a balanced diet, can help prevent many of these diseases.

Additionally, quarantining any new fish before introducing them to an established aquarium can help prevent the spread of diseases.

If you notice any signs of illness in your fish, it is important to take prompt action, such as quarantining affected fish and seeking appropriate treatment.


Here are some frequently asked questions that people have about setting up their first fish tank!

Why Do You Need To Wait Before Adding Fish To Your Tank?

The reason you need to wait before adding fish to your fish tank, is because the tank needs to cycle completely. Without this cycling, then your fish may end up being poisoned by ammonia, and it could wipe all of them out in a matter of hours.

What Temperature Should Your Fish Tank Be?

Generally speaking, tropical fish tanks are normally between 75-80°F. Cold water fish tanks are normally between 60-75°F. And saltwater fish tanks are normally kept between 78-82°F. However, it also depends on the fish you plan on keeping.

How Many Fish Can You Keep In Your Tank?

A very general rule of thumb is 1 inch of fish per gallon of water in your tank. Although, you should ALWAYS check the needs of your individual fish, as some small fish need a lot of swimming space.


As you can see A LOT goes into caring for your fish. However, setting up a fish tank doesn’t have to be difficult! In fact, I find the hardest part of setting a fish tank up is just being patient!

If you have any questions then feel free to ask! The best place to ask is in the Facebook group which I’m always keeping an eye on!

Otherwise, make sure to check out the rest of the website. Otherwise, have a great day!

Ultimate Betta Fish Care Guide
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