Best Fish For 20 Gallon Tanks: 78 Best Choices

Setting up a 20-gallon fish tank is an exciting adventure full of possibilities. You’re not just setting up a tank; you’re building a vibrant community of fish that will bring you joy. But with so many fish out there, it can be challenging to pick the right ones.

So, let’s explore some of the best fish to fill your 20-gallon tank and why they’re worth considering!

Table of Contents

Best Fish For 20 Gallon Tanks

Now, let’s go over the best options for your 20-gallon tank and what you should know about them!

Swordtails

Swordtails Care Sheet

Swordtails are the elegant royalty of your aquarium. They have long, slender bodies, and males have a long, sword-like extensions on their tail. They’re easy to care for and make great pets for beginners. In your 20-gallon tank, they’ll thrive if you provide a mix of live plants and open swimming space.

Swordtails are omnivores, which means they’re not too picky about food. They’ll delight in flakes, pellets, and even live or frozen treats like brine shrimp and daphnia. Just remember, if you’ve got males, they can sometimes be a tad territorial, so consider having a few more females to balance things out.

Mollies

Molly Fish Care Sheet

Mollies are like the social butterflies of the aquarium world. They’re incredibly interactive and thrive when they have companions to swim with. In your 20-gallon tank, a mix of males and females is a good idea to keep things harmonious. Mollies enjoy some plant cover but still need plenty of swimming space. 

Water conditions similar to swordtails work well for Mollies too. Mollies are also omnivores, gobbling up flakes, pellets, and various live or frozen goodies. Mollies can survive in brackish water to some extent, which makes them a good choice for fishkeepers if you want to add a bit of salinity to their tank.

Rummy Nose Tetras

Rummy Nose Tetras Care Sheet

With their striking red heads and translucent bodies, Rummy Nose Tetras are hard to miss. These tetras are quite sensitive to water conditions, so maintaining good water quality is essential. These tetras love to school, so having at least six of them is recommended. 

The vibrant red color on their heads is a great indicator of their well-being. When they’re comfortable, the red stays vivid. Rummy nose tetras are omnivores, but their diets lean more towards flakes, micro pellets, and small live or frozen foods like brine shrimp. 

Bolivian Rams

Bolivian Ram Care Sheet

Bolivian rams are known for their gentle demeanor and intricate patterns. These cichlids are relatively peaceful, making them suitable for a community setup. In your 20-gallon tank, make sure to provide plenty of hiding spots using driftwood, rocks, and plants. They prefer slightly soft to neutral water conditions as well.

Bolivian rams are omnivores with a preference for high-quality pellets, flakes, and small live or frozen foods. They’re also known to form pairs and might even grace you with the sight of some courtship and parenting behavior.

Rainbow Kribensis

Rainbow Kribs Care Sheet

Rainbow Kribensis have dazzling colors and interesting behaviors that can captivate anyone’s attention. These dwarf cichlids are quite adaptable and can thrive in various water conditions. Aim for a slightly acidic to neutral pH and provide plenty of hiding spots using plants and decorations.

Rainbow Kribensis are omnivores, so they’ll enjoy a mix of flakes, pellets, and live or frozen treats. These fish are fun to watch as they dig and rearrange the substrate in your tank. They’re like little aquarium landscapers!

Honey Gouramis

Honey Gourami Care Sheet

Honey gouramis have shimmering golden bodies and peaceful demeanor, they bring an air of tranquility to your tank. These gouramis thrive in slightly acidic to neutral water conditions with plenty of plants for cover. Keep the water temperature on the warmer side to keep them happy.

Honey gouramis are labyrinth fish, which means they can breathe air from the surface. They’re generally peaceful and can be kept in small groups. Their diet includes small live or frozen foods like daphnia and brine shrimp, but they’ll also enjoy high-quality pellets and flakes.

Paradise Fish

Paradise Fish Care Sheet

Paradise fish can bring a burst of energy to your fish tank. Labyrinth fish are known for being territorial, so providing plenty of hiding places and plants can help them coexist peacefully. Paradise fish appreciate slightly acidic to neutral water conditions. 

Their diet consists of flakes, pellets, and live or frozen treats like bloodworms and brine shrimp and daphnia. Males are especially colorful and might exhibit some territorial displays, so choose tankmates wisely.

Thick Lipped Gourami

Thick Lipped Gourami Care Sheet

Thick-lipped gouramis are famous for their distinctive appearance and unique behaviors, and they surely add a touch of mystery to your tank. These gouramis thrive in slightly acidic to neutral water conditions and enjoy plenty of greenery. Also, Thick Lipped Gouramis can coexist well with other non-aggressive species.

Provide them with a varied diet of high-quality flakes, pellets, and occasional live or frozen treats like brine shrimp. Their specialized “thick lips” are adapted for feeding on biofilm and small invertebrates, making them really interesting to observe.

Apistogramma Cichlids

Apistogramma cichlids have absolutely stunning colors and complex behaviors and they offer a captivating spectacle. These dwarf cichlids hail from South America and thrive in slightly acidic to neutral water conditions. They appreciate heavily planted tanks with plenty of hiding spots. 

Apistogrammas are known for their unique courtship and parenting behaviors, making them an intriguing addition to your tank. Their diet includes high-quality flakes, pellets, and small live or frozen foods like brine shrimp. 

Dwarf Flag Cichlids

With their flowing fins and vibrant colors, Dwarf flag cichlids are like graceful dancers that add elegance to your fish tank. These cichlids prefer slightly acidic to neutral water conditions and thrive in well-planted tanks with plenty of hiding spots. 

Dwarf flag cichlids are generally peaceful and can be kept in community tanks. They eat high-quality flakes, pellets, and small live or frozen foods like daphnia and brine shrimp. They may form pairs and exhibit some territorial behavior, so give them plenty of space and hiding places to maintain harmony in the tank.

Egyptian Mouthbrooders

Egyptian mouthbreeders are African cichlids that do really well in slightly alkaline environments. They’ve got an interesting behavior where the females take care of and transport their eggs in their mouths, showing a lot of love for their little ones.

To cater to their needs, offer them a menu of high-quality pellets, flakes, and small live or frozen treats, like brine shrimp and daphnia. With Egyptian mouthbreeders around, your tank transforms into an engaging spectacle of aquatic family dynamics.

Electric Blue Ram

Electric Blue Ram Care Sheet

Electric blue rams have vibrant blue shade and friendly personalities that make them an absolute delight. They do well in well-planted tanks with plenty of hiding places to explore;  their happy place.

Now, here’s a tip: they’re finicky about water conditions, so keep things in tiptop shape. When it comes to food, they’re all about high-quality flakes, pellets, and small live or frozen treats like brine shrimp. With electric blue rams around, your tank will be electrified with their striking presence.

Golden Dwarf Cichlid

Golden dwarf cichlids are like radiant stars in your aquatic galaxy. Their golden hues and spirited behaviors add a touch of magic to your tank. They prefer slightly acidic to neutral water conditions, which is their sweet spot. To make their stay absolutely marvelous, provide them with a lushly planted tank with plenty of hiding spots.

Golden dwarf cichlids are known for their friendly nature, so they’re great for a community setup. When it’s time to feast, they’ll dive into high-quality pellets, flakes, and dabble in small live or frozen treats like brine shrimp.

Honduran Point Cichlid

With their intricate patterns and unique habits, Honduran Point Cichlids are the life of the party in your tank. Now, to create their perfect haven, make sure to add rocks and caves for hiding spots. However, remember that they tend to be quite territorial, so a well-designed tank layout is essential.

Their menu includes high-quality pellets, flakes, and petite live or frozen treats like brine shrimp. With Honduran point cichlids around, your tank becomes a canvas for their captivating stories.

Masked Julie

Masked Julies are add a touch of mystery to any aquarium. And with their unique markings and vibrant colors, they’re head turners. These cichlids are native to Lake Tanganyika, where they prefer slightly alkaline water. So, to create a suitable environment for them in your tank, be sure to include plenty of hiding places, like rocks and caves. 

Masked Julies are generally peaceful fish, but it’s always best to have a well-planned tank setup to ensure harmony. And when it comes to feeding, they’ll enjoy a variety of foods, including high-quality pellets, flakes, and live or frozen treats.

Rainbow Cichlid

Meet the rainbow cichlid, the colorful fish that will add life to your tank. They come from Central America and love slightly alkaline to neutral water. 

Give them plenty of hiding places and decorations, as they’re social fish. They eat high-quality pellets, flakes, and sometimes live or frozen food like brine shrimp. With their bright colors and friendly personality, these fish will make your underwater world a masterpiece.

Keyhole Cichlid

Keyhole cichlids are peaceful fish that are perfect for adding a touch of serenity to your 20-gallon aquarium. They have distinctive keyhole-shaped markings and prefer slightly acidic to neutral water conditions. They thrive in a well-decorated tank with lots of hiding spots. 

Creating a peaceful environment is key to their happiness. Keyhole cichlids are not too fussy eaters and will enjoy high-quality pellets and flakes, as well as small live or frozen treats like brine shrimp.

Lemon Cichlid

With their bright lemon-yellow colors and lively behaviors, lemon cichlids are the sunny personalities of your tank. These cichlids prefer slightly alkaline to neutral water conditions, like their natural habitat. And to keep them thriving, create a well-decorated tank with plenty of hiding spots.

Lemon cichlids are peaceful fish that make great additions to community tanks. They eat high-quality pellets, flakes, and small live or frozen foods like brine shrimp. Their cheerful colors and friendly interactions make them a joy to watch in your tank.

Cherry Barbs

Cherry Barb Care Sheet

Cherry barbs are lively and playful fish that add a vibrant energy to any aquarium. They’re small schooling fish that thrive in slightly acidic to neutral water conditions. To keep them happy, provide them with a tank with plants, decorations, and open spaces to swim.

Cherry barbs are known for their active behavior and do best in groups. Also, their diet includes high-quality flakes, pellets, and small live or frozen foods like brine shrimp. With their playful antics and vivid colors, cherry barbs are sure to turn your aquarium into a lively celebration.

Peacock Gudgeons

Peacock Gudgeon Care Sheet

Introducing the peacock gudgeons that’ll captivate your attention with their intricate patterns and vibrant colors!  These gudgeons prefer slightly acidic to neutral water conditions and thrive in a well-decorated tank with plenty of hiding spots. 

Peacock gudgeons are originally from Southeast Asia, and as omnivores, their diet includes high-quality pellets, flakes, and small live or frozen treats like brine shrimp and daphnia.

Splendid Killifish

With their intricate patterns and vibrant colors, Splendid Killifish are like living art in motion. These killifish are known for their unique breeding behavior that’s very interesting to watch. Unlike other fish that lay eggs, lay their eggs directly on damp substrate, creating a haven for their offspring.

To keep them in their prime, provide them with slightly acidic to neutral water conditions and a well-decorated tank with plenty of hiding spots. Their diet thrives on small live and frozen foods like daphnia and brine shrimp. These killifish are like living works of art, adding a touch of wonder to your tank.

Black Neon Tetras

Black Neon Tetra Care Sheet

Black neon tetras are beautiful, fascinating fish that can add a touch of elegance to any aquarium with. They have a striking contrast of black and neon-blue, and they school together in tight-knit groups that gracefully glide through the water. 

To create the perfect environment for your black neon tetras, keep the water slightly acidic to neutral and provide plenty of plants and decorations for them to explore. They eat high-quality flakes, small live foods, and the occasional treat like brine shrimp. 

Kuhli Loaches

Kuhli loach care sheet

Kuhli loaches are fascinating nocturnal fish that bring charm to your tank. Their unconventional appearance and entertaining habits will keep you entertained day and night. While they might be shy during the day, they come out to play at night, exploring every part of your tank. 

And to create a comfortable environment for their escapades, provide them with slightly acidic to neutral water conditions and plenty of hiding spots. Their diet includes sinking pellets, frozen foods, and live treats like bloodworms. 

Emperor Tetras

Emperor Tetra Care Sheet

Back to a classic favorite – the emperor tetra. The emperor tetra is a popular fish that’s named after the Emperor River in Brazil. Emperor tetras are peaceful and social fish that will add balance to your aquarium. Also, they’re schooling fish, so they’re best kept in groups.

To create a healthy environment for them, the water should be slightly acidic to neutral and there should be plenty of plants for them to swim around in. They eat high-quality flakes, freeze-dried foods, and frozen treats. 

Red Eye Tetras

Redeye Tetra Care Sheet

Red eye tetras are lively and active fish that will add color and excitement to your aquarium.  With their shimmering bodies and striking red eyes, they’re like living jewels that catch every glint of light. 

To care for red eye tetras, keep the water slightly acidic to neutral and provide plenty of open swimming space. They eat high-quality flakes, small live foods, and frozen treats. Red eye tetras are a joy to watch and make a great addition to any aquarium.

X-Ray Tetras

X-Ray_Pristella Tetra Care Sheet

Meet the X-ray tetra, a mesmerizing fish that will add a touch of magic to your aquarium with their transparent bodies and ghostly appearance. The “X-ray” in their name comes from the fact that their internal organs are visible through their clear bodies.

The X-ray tetra is a great choice for beginner aquarium owners. They thrive in well-planted tanks with hiding spots and enjoy high-quality flakes, small live foods, and frozen treats like brine shrimp.

Bleeding Heart Tetra

Bleeding Heart Tetra Care Sheet

The bleeding heart tetra is a charming fish that will add a touch of romance to your aquarium. With their red heart-shaped mark against a silver backdrop, they’re sure to turn heads. These fish are also known for their captivating courtship behavior. During mating, the males engage in a dance, vibrating and fluttering their fins to impress the females.

To keep your bleeding heart tetras happy and healthy, provide them with slightly acidic to neutral water conditions and plant cover. They’ll also appreciate a diet of high-quality flakes, small live foods, and occasional treats.

Blue Tetras

Experience the peaceful world of blue tetras, which add a calming touch to your aquatic display. Their delicate blue hues create a relaxing atmosphere in your tank. These tetras thrive in slightly acidic to neutral water conditions, seeking shelter among well-placed decorations. Notably, they have an iridescent skin layer that reflects light, giving them a captivating shimmer. 

And as for their diet, make sure to feed them high-quality flakes, small live foods, and occasional servings of frozen treats!

Cardinal Tetras

Cardinal Tetra Care Sheet

Cardinal tetras are noble fish that add color and grace to any aquarium. They have vibrant red and blue stripes and form a symbiotic relationship with floating plants, which provide shade and mimic their natural habitat. 

To keep them healthy, maintain slightly acidic to neutral water conditions and provide plants and open spaces in your tank. Cardinal tetras eat high-quality flakes, small live foods, and occasional treats. They’ll elevate your tank with regal charm and timeless beauty.

Toucan Tetras

Toucan tetras are subtle marvels that will add grace and tranquility to your tank. Their distinct black markings and shimmering silver bodies create an artistic contrast that draws the eye. Native to the Rio Orinoco basin in South America, they thrive in slightly acidic to neutral water conditions. 

A well-planted tank with open swimming spaces is ideal for these peaceful fish. And when it comes to their food preferences, Toucan tetras enjoy high-quality flakes, small live foods, and occasional frozen treats.

Bloodfin Tetra

Bloodfin Tetra Care Sheet

Discover the bloodfin tetra – the red-tinged wonders in your underwater haven. With their distinctive red lower fins, they create a captivating visual effect as they glide through the water. These tetras are from the Paraguay and Paraná river basins in South America and prefer slightly acidic to neutral water conditions

Bloodfin tetras are social beings, often found schooling together in the wild. To recreate this, maintain a group of these tetras in your tank. Their diet includes high-quality flakes, small live foods, and frozen treats. 

Penguin Tetra

Penguin Tetra Care Sheet

Meet the penguin tetra, the monochrome gems of your aquarium. With their black and white tuxedo markings, they’re formal and elegant. These tetras hail from the rivers and streams of South America. They thrive in slightly acidic to neutral water, like their natural habitat. 

Penguin tetras shine in a well-planted tank with plenty of swimming space. Their peaceful nature makes them compatible with other fish. They eat high-quality flakes, small live foods, and frozen treats. Penguin tetras add a touch of sophistication and contrast to your aquatic showcase.

Silvertip Tetra

Silvertip Tetra Care Sheet

The silvertip tetra is another beautiful fish for 20 gallon tanks with a silvery body and black tips on its fins. It’s native to the Amazon River basin in South America, where it lives in slightly acidic to neutral water. Silvertip tetras are peaceful fish that do well in community tanks.

They’re easy to care for and eat a variety of foods, including flakes, live food, and frozen treats. If you’re looking for a beautiful and easy-to-care-for fish, the silvertip tetra is a great choice.

Lemon Tetra

Lemon Tetra Care Sheet

The lemon tetra is a peaceful fish that will add a touch of sunshine to your tank. They’re native to South America and have yellow bodies with black markings. They thrive in slightly acidic to neutral water conditions and prefer a well-planted tank with plenty of open swimming space. 

Lemon tetras are a great choice for community tanks and are easy to care for. They eat high-quality flakes, small live foods, and occasional frozen treats.

Glofish Tetra

Glofish Tetra Care Sheet

Glofish tetras have striking fluorescent hues that transform your tank into a vibrant showcase of colors. These tetras are native to the Amazon River basin in South America. They adapt well to slightly acidic to neutral water conditions, creating an environment that reflects their natural habitat. 

Glofish tetras do well in a well-decorated tank with plenty of open space to swim. Their small size and peaceful nature make them compatible with a variety of other fish. They eat high-quality flakes, small live foods, and frozen treats. 

Serpae Tetra

Serpae Tetra Care Sheet

Serpae tetras are known for their striking red and black markings. They’re native to the Paraguay and Paraná river basins in South America. They prefer slightly acidic to neutral water conditions, similar to their native waters. Serpae tetras like a well-planted tank with hiding places, which provides them a safe haven to explore.

They’re known for their feisty behavior, and they establish a pecking order within their group. Their diet includes high-quality flakes, small live foods, and frozen treats. Serpae tetras infuse your tank with a burst of color and lively activity.

Red Phantom Tetra

Red Phantom Tetra Care Sheet

The red phantom tetra is a beautiful and mysterious fish that will add a touch of elegance to your aquarium. These fish are native to South America and thrive in slightly acidic to neutral water conditions.

They also love well-planted tanks with plenty of hiding spots, where they can school together and feel safe. 

Blind Cave Tetra

Blind Cave Tetra Care Sheet

Blind cave tetras, with their colorless appearance and adapted eyes, are a unique example of evolution in the absence of light. These tetras are native to the underground waters of Mexico, where they thrive in slightly acidic to neutral water conditions. 

Because Blind Cave Tetras are cave-dwellers who are comfortable in dark, murky environments, they don’t need light to see. Make sure to also add lost of hiding spots to make them even more comfortable. And for their diet, they usually eat a variety of foods, including flakes, live food, and frozen treats. 

Panda Tetra

Panda Tetra Care Sheet

Meet the panda tetra, the charming pandas of the fishkeeping world. With their black and white bodies, they look like mini pandas taking a dip. These little fish come from South America, where they prefer soft water. When creating their cozy habitat, add some plants and hiding spots. 

They’re social fish, so keeping a small group of them will keep them happy. At mealtime, feed them a mix of quality flakes, small live treats, or frozen food.

Tiger/Albino Tiger Barbs

Tiger Barb Care Sheet

Meet the tiger and albino tiger barbs – the striped fish that will add some spunk to your tank. These fast fish with bold black stripes come from Southeast Asia and can live in slightly hard water. They’re always on the move, so give them a big tank to swim around in. 

Remember, they’re not loners, so keep them in a group. They eat a variety of food, including flakes, small live food, and frozen food. Tiger and albino tiger barbs are a great addition to any tank.

Checker Barbs

Checker Barb Care Sheet

Checkered barbs are cool fish with a fun checkerboard pattern. They come from Asia and like their water with a bit of hardness. A well-decorated tank with hiding spots is perfect for their 20 gallon tank. They’re also friendly and like to be around other barbs.

Make sure to feed them good flakes, live treats, or frozen snacks. Checkered barbs add a touch of pattern and life to your underwater world.

Pentazona Barbs

Pentazona Barb Care Sheet

Pentazona barbs are beautiful fish that add a splash of color to your tank. They’re native to Southeast Asia and have a mix of green, yellow, and black shades. They’re graceful swimmers and like to explore their surroundings, so a well-planted tank is perfect for them. 

Also, Pentazona barbs are social fish and do best in groups. They’re easy to care for and eat a variety of food, including flakes, live food, and frozen food. Overall, if you’re looking for a beautiful and easy-to-care-for fish, pentazona barbs are a great option.

Glofish Barbs

Now we have the glofish barbs. With their radiant fluorescent shades, they transform your tank into a vivid spectacle. These barbs are bred from zebrafish and are all about adding a pop of color. They’re happy in slightly hard water, and a lively tank with room to explore suits their active nature. 

Glofish barbs thrive when they’re with their friends, so keeping them in a group is a good idea. As for their meals, they’re not too picky—quality flakes, small live treats, or frozen bites all work. Glofish barbs light up your tank with vibrant energy and a touch of brilliance.

Golden Barbs

Golden Barb Care Sheet

Golden barbs are colorful, playful fish that are native to Southeast Asia. They’re low maintenance for and make a great addition to any aquarium. They prefer slightly hard water conditions and should be kept in groups of at least six fish. A well-decorated tank with open spaces is ideal for these active fish.

As for their menu, offer up quality flakes, live bites, and frozen treats. 

Peppered Corydoras

Peppered Corydoras Care Sheet

Meet the peppered corydoras, the gentle cleaners of your fish tank. These small fish are native to South America and have distinctive pepper-like markings. They’re bottom-dwellers that eat leftover food and debris, so they’re great for keeping your tank clean. 

Peppered corydoras are social fish that like to live in groups, so it’s best to get at least six of them. Additionally, Peppered Corys appreciate a well-planted tank with open spaces to rest. You can feed them sinking pellets, live snacks, or frozen bites. 

Adolfo Corydoras

Adolfo's Corydoras Care Sheet

Adolfo corydoras are elegant fish that dance in your 20 gallon tank. Their intricate patterns and graceful movements create a mesmerizing display. These fish come from the rivers of South America, where they prefer slightly acidic to neutral water conditions.

Adolfo corydoras are known for their peaceful nature, so they make great companions for other fish. Their diet includes sinking pellets, live food, and frozen treats. And don’t forget, well-decorated tank with hiding spots and open spaces will make them happy. 

Agassizi Corydoras

Agassizi's Corydoras Care Sheet

Say hello to the Agassizi corydoras – the curious explorers of your fish tank. With their vibrant colors and lively patterns, they’re like tiny adventurers on a quest. These corys are native to the Amazon basin, where they thrive in slightly acidic to neutral waters. They’re often seen swimming around the bottom of your tank. 

Agassizi corydoras are friendly fish who like to be around other corys. They like to explore their tank, so it’s important to have plenty of plants, hiding spots, and open areas for them to swim around in. You can feed them sinking pellets, live snacks, or frozen bites.

Albino Corydoras

Albino Corydoras Care Sheet

Meet the albino corydoras, the gentle, white fish that will add a touch of beauty to your fish tank. They come from South America and prefer slightly acidic to neutral water. These bottom-dwellers are always looking for food on the bottom of the tank, and they’re known for their calm nature.

They’re social creatures that like to be in groups, so it’s best to keep them with at least five other fish. They need a well-furnished tank with hiding spots and open swimming areas. You can feed them sinking pellets, live food, or frozen treats. Albino corydoras are a great addition to any fish tank.

Blue Spotted Corydoras

Introducing the blue spotted corydoras! These little fish are a great addition to any 20-gallon tank. They’re also native to South America and like to live in slightly acidic to neutral water. They’re peaceful fish that like to swim near the bottom of the tank, and it’s always best to keep them in groups. 

They’ll eat sinking pellets, live food, and frozen treats. Blue spotted corydoras are a great way to add elegance and tranquility to your tank.

Delphax Corydoras

Delphax corydoras are peaceful bottom-dwelling fish that add a touch of mystery to your aquarium. They have unique patterns and muted colors, and they enjoy exploring the bottom of the tank, scavenging for food. 

Also, a tank with plants, hiding spots, and open areas is perfect for your Delphax Corydoras. Their diet includes sinking pellets, live food, and frozen treats

Elegant Corydoras

Just like what their name suggests, Elegant corydoras are graceful fish from South America that are truly stunning. These Corydoras get along well with other tank mates, and they enjoy a well-decorated tank with hiding spots and open spaces to swim.

Corydoras are social fish that like to hang out in groups. They’ll eat sinking pellets, live food, and frozen treats. If you’re looking for a beautiful and peaceful fish for your aquarium, the elegant corydoras is a great choice!

Schwartz’s Corydoras

Schwartz's Corydoras Care Sheet

Schwartz’s corydoras are the charming explorers of your underwater world. With their distinctive patterns and sociable behavior, they’re the life of the aquatic party. Schwartz’s corydoras are active bottom-dwellers, and you’ll often see them swimming around for food. 

Schwartz’s corys are peaceful creatures, so they’re great tankmates for other fish. A tank with plants, hiding spots, and open swimming spaces is perfect for their lively nature. Their diet includes sinking pellets, live food, and frozen treats. Schwartz’s corydoras add both charm and energy to your 20 gallon tank.

Sterba’s Corydoras

Sterba's Corydoras Care Sheet

Sterba’s corydoras are beautiful, peaceful fish that are perfect for any aquarium. They have bold patterns and vibrant colors, and they love to swim around and explore their surroundings. Sterba’s corydoras are also very social fish, and they get along well with other fish in community tanks.

And as for their food requirements, make sure to feed them a variety of live, frozen, and flake foods.

Clown Pleco

Clown Pleco Care Sheet

Meet the clown pleco, a friendly fish with a black and white/orange pattern. They’re from South America and love to eat algae. They’re small but playful, and they make a great addition to any tank. 

Give them a well-furnished tank with hiding spots and driftwood, and feed them algae wafers, sinking pellets, or fresh veggies. Clown plecos are sure to add a touch of fun to your aquatic life!

Black/Barred Danio

Black/barred danios are a sight to behold, with their sleek black stripes and vibrant colors. They’re native to Southeast Asia, where they thrive in slightly hard water conditions. These fish are always on the go, darting around the tank in joyful bursts. 

They’re social creatures and love the company of other danios. A well-decorated tank with open swimming spaces is perfect for these lively fish. Black/barred danios love to eat quality flakes, small live bites, and frozen treats.

Glofish Danio

Say hello to the glofish danio – the neon stars of your 20 gallon tank! With their radiant fluorescent colors, they’ll transform your tank into a celestial light show. These danios are bred from zebrafish, and they’re all about adding a touch of cosmic flair. They’re content with slightly hard water conditions. 

A tank with open spaces for their playful swimming style suits them well. Glofish danios thrive in a group, so keep them in good company. As for their meals, they’re not too picky – quality flakes, small live bites, or frozen nibbles all work. 

Malabar Danio

Malabar Danio Care Sheet

Discover the Malabar danios! These Danios are famous for their vibrant colors and lively patterns; they’re like little explorers discovering new territories. They come from the rivers of India, where they enjoy slightly hard water conditions. 

Malabar danios are also known for their energetic nature, often seen swimming throughout the tank. They’re social beings, thriving in a group environment. A tank with plants, open swimming spaces, and driftwood will make them happy. Also, their diet includes quality flakes, small live bites, and frozen treats. 

Rose Danio

Rose Danios are pretty, peaceful fish that like to swim in schools. They’re easy to care for and will surely add a touch of beauty to your 20-gallon aquarium. They’re native to Southeast Asia and prefer slightly hard water. A well-planted tank with open spaces is perfect for them. 

They eat a variety of food, including flakes, live food, and frozen food. Rose danios are a great choice for any aquarium.

Knight Goby

Fan Dance_Knight Goby Care Sheet

Check out the knight goby, the fish that adds a touch of mystery to your 20-gallon underwater kingdom. Originating from brackish waters, these gobies are unique choices that thrive in conditions between freshwater and saltwater. 

They have a thing for hiding spots and sandy substrates, which mimics their natural habitat. A mix of algae-based foods and live bites make up their diet. 

American Flag Fish

American Flagfish Care Sheet

Check out the American flag fish! These vibrant little patriots add a touch of national pride to your 20-gallon aquarium. With their red, white, and blue colors, they look like a living flag waving beneath the water’s surface. These North American fish thrive in slightly hard water conditions. 

Their territorial behavior gives them a unique and engaging personality. American flag fish do well in well-decorated tanks with plants and hiding places. They eat both plant-based and protein-rich foods. These flag fish add a splash of color and a dash of uniqueness to your aquarium.

Christys Killifish

Introducing Christys killifish, the colorful and mesmerizing fish that will take center stage in your fish tank. These beautiful fish hail from Africa, where they often live in temporary water bodies that test their adaptability. But don’t worry, Christys killifish are resilient and can thrive in a variety of water conditions. 

To keep your Christys killifish happy, give them a well-planted tank with open swimming spaces. They’ll eat a variety of food, including quality flakes, live food, and frozen treats like tubifex and bloodworms. Christys killifish are a great addition to any aquarium, and they’re sure to bring you years of enjoyment.

Golden Wonder Killifish

Golden Wonder Killifish Care Sheet

With their glimmering gold tones and intricate patterns, Golden Wonder Killifish will grace your 20-gallon aquarium with their radiant beauty. Originating from Africa, these killifish inhabit diverse water bodies, showing off their adaptability.  Golden wonder killifish are renowned for their hardiness and ease of care.

They’re peaceful companions that thrive in community setups. A well-furnished tank with plants and hiding spots provides them a comfortable home. Their varied diet includes high quality flakes, live bites, and occasional frozen treats. 

Red Chinned Panchax

Red Chinned Panchax Care Sheets

With their bright red chins and active personalities, Red-chinned panchax will add a burst of energy and color to your 20-gallon aquarium. These panchax come from both Africa and Asia, so they add a global touch to your aquatic collection. Known for their striking appearance, they’re a visual treat to watch.

Red-chinned panchax thrive in slightly acidic to neutral water conditions. Their peaceful nature makes them great additions to community tanks. Also, a tank filled with lush plants and open swimming areas suits their energetic personality. And of course, their diverse diet includes quality flakes, live food, and frozen treats. 

Yabassi Lampeye Killifish

Yabassi lampeye killifish are like shimmering gems with their vibrant colors and distinct markings. They’re from West Africa and live in both freshwater and brackish environments. Yabassi lampeyes are known for their iridescent appearance, which makes them seem to reflect the colors around them.

A well-planted tank with subdued lighting is perfect for these Killifish. Also, their diet includes quality flakes, live food, and frozen treats.

Galaxy Loach

Galaxy loaches are cool fish that look like they came from outer space. They’re small, non-aggressive, and easy to care for. They like to swim around and explore every part of their tank, and they’re always up for a game of hide-and-seek. 

And when it comes to food, make sure to give your galaxy loaches a variety of live, frozen, and dried foods.

Panda Loach

Meet the panda loach, the adorable little fish that will steal your heart and make your 20-gallon aquarium a paradise. With their distinctive black and white markings, they look just like the beloved panda bears. These loaches come from Southeast Asia, where they thrive in slightly acidic to neutral water conditions. 

Panda loaches are known for their peaceful and social nature, and they’re often seen in groups exploring their environment. They appreciate a well-decorated tank with hiding spots and plants. Their diet includes sinking pellets and live food. 

Sumo Loach

With their stocky bodies and distinctive patterns, sumo loaches will add a touch of humor and personality to your 20-gallon tank. These loaches come from Southeast Asia, where they thrive in slightly hard water conditions.

Sumo loaches are known for their playful antics, often seen rooting around in the substrate for food. They like a tank with plenty of hiding places, plants, and open spaces for their playful behavior. Their diet includes brine shrimp, daphnia, bloodworms, and tubifex worms.

Elegant Pencilfish

Elegant pencilfish are beautiful, peaceful, and easy to care for. They’re a great addition to any 20-gallon aquarium. These graceful swimmers add a touch of sophistication to your tank with their slender bodies and delicate coloring. Originating from South America, they prefer soft and slightly acidic water conditions. 

Remember though, Elegant pencilfish like to swim in small groups, so make sure you get at least six of them. Also, they appreciate a well-planted tank with subdued lighting and open swimming areas. Their diet includes brine shrimp, daphnia, bloodworms, tubifex worms, and flake food. 

Three Lined Pencilfish

Three Lined Pencilfish Care Sheet

Three-lined pencilfish are graceful, elegant fish that add a touch of beauty to your aquarium. They’re native to South America and prefer soft, slightly acidic water. These peaceful fish are often seen in small groups, and they like well-planted tanks with subdued lighting. 

And when it comes to their diet, remember that three-lined pencilfish eat quality flakes, live food, and occasional frozen treats. 

Celebes Rainbowfish

Celebes Rainbowfish Care Sheet

Meet the Celebes rainbowfish – the vibrant wonders that light up your 20-gallon aquatic landscape. With their radiant colors and unique patterns, they’re like living rainbows dancing beneath the water’s surface. Hailing from Indonesia, these rainbowfish thrive in slightly alkaline water conditions. 

The ideal environment for Celebes rainbowfish includes an aquarium with enough space to swim and vegetation to provide shelter. Also, they thrive on a diet that consists of high-quality flakes, live food, and frozen snacks.

Redfin Dwarf Rainbowfish

Redfin Dwarf Rainbowfish are little gems from Australia that are known for their fiery red fins and striking hues, which add liveliness to any fish tanks they’re in. With their playful and active nature, they love to move around and enjoy a well-decorated tank with ample space to swim and hide. 

To keep them healthy and happy, feed them a balanced diet with a variety of different foods, such as high-quality flakes, live bites, and brine shrimp. 

Blueline Rasboras

The blueline rasboras are a stunning addition to any fish tank, bringing an air of refinement with their beautiful blue stripes and calm temperament. Originating from Southeast Asia, these fish flourish in water that is slightly acidic to neutral.

Blueline rasboras thrive in a tank with plants and open swimming spaces, allowing them to display their natural behaviors. Their diet includes quality flakes, live bites, and frozen treats like Brine shrimp and Bloodworms. 

Brilliant Rasboras

Brilliant Rasbora Care Sheet

Brilliant rasboras are dazzling fish that add a burst of color to your aquarium. They’re peaceful and like to swim in schools, so they’re a great addition to any tank. Brilliant rasboras prefer slightly acidic to neutral water conditions and need a well-planted tank with open spaces for swimming. 

And to keep your Brilliant Rasboras happy, make sure that they eat quality flakes, live bites, and frozen treats like blood worms.

Eyespot Rasboras

Eye Spot Rasbora Care Sheet

Eyespot rasboras are mesmerizing fish that add an element of mystery to your aquarium. They’re originally from Southeast Asia and love slightly acidic water. They’re peaceful creatures and love to explore. Just make sure to give them plenty of hiding places and vegetation. 

Glowlight Rasbora

Glowlight Rasbora Care Sheet

Glowlight rasbora are stunning Rasboras that can add a magical touch to your 20-gallon tank. They originate from Southeast Asia and require slightly acidic water in order to thrive. 

Glowlight rasboras prefer a well-planted tank and can be fed high-quality flakes, live food, and frozen treats. Also, they’re social, and they enjoy swimming in groups, so make sure you have enough space for them to move around. 

Graceful Rasbora

If you’re looking for some elegant swimmers to add sophistication to your 20-gallon tank, consider the graceful rasbora! They’re native to Southeast Asia and prefer slightly acidic to neutral water conditions. 

They’ll thrive in a well-equipped tank with plants and open spaces, and enjoy a diet of high-quality flakes, live food, and frozen treats. With peaceful temperaments, Graceful Rasboras swim with smooth, gentle movements. 

Red-Tailed Rasbora

Red-Tailed Rasbora Care Sheet

Meet the red-tailed rasbora, a burst of color and liveliness for your 20-gallon aquarium. These fish have fiery red tails and are like passionate flames in your tank. They come from Southeast Asia and prefer slightly acidic water. Red-tailed rasboras are social and active, often swimming together in large groups. 

They thrive in a well-decorated tank with plants and lots of open space for swimming. Their diet should consist of quality flakes, live food, and frozen treats.

Scissortail Rasbora

Scissortail Rasbora Care Sheet

The scissortail rasbora is a really pretty fish that would look great in your 20-gallon tank. They have a cool tail and move around gracefully. They come from Southeast Asia and like slightly acidic water. 

They’re peaceful and active, and you’ll see them swimming around a lot. To keep them happy, make sure your tank has plants and open space. Make sure to feed them good flakes, live food, and some occasional frozen treats like brine shrimp or blood worms. 

How To Setup A 20 Gallon Fish Tank

No matter if you’re new or experienced, setting up a fish tank needs planning. In this guide, we’ll show you step-by-step how to set up a great home for your fish.

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Finding the Right Spot

First, pick a good place for your tank. Make sure it’s flat, strong, and away from the sun or big temperature changes. This will keep your fish and their home safe.

Getting the Stuff You Need

Gather things like a filter, heater (if your fish need it), and light. Choose pretty things for your fish to enjoy, like rocks and plants. These things make the tank look nice and feel comfy.

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Making the Tank Nice

Put clean stuff at the bottom of the tank. Add things like rocks and plants to make it feel like home for the fish. Make hiding spots, so the fish can feel safe.

Adding Water and Making It Safe

Put water in the tank, but make sure it’s safe for the fish. To make sure that the water is safe you should use a water conditioner to remove any chlorine and chloramines.

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Making the Water Clean

A filter helps keep the water clean and fresh for the fish. Follow the instructions to put the filter in the tank.

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Testing the Water

Use a test kit to check if the water is good for your fish. Fish like certain things in the water, so it’s important to know if it’s right.

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Adding the Fish and Watching Them

Once the tank is ready, bring in your fish! Start with just a few fish that like each other. Watch how they swim and have fun in their new home.

Feeding and Keeping Clean

Give your fish food they like and only as much as they need. Sometimes, you’ll need to clean the tank and change a little bit of the water to keep it nice for the fish.

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Enjoying Your Fish

Over time, you’ll see your fish grow and have their own fishy adventures. Watching them is a great way to learn more about them and take care of them.

FAQ

What Size Fish Can You Put In A 20 Gallon Tank?

You should avoid putting fish bigger than 6-7 inches in your tank as 20 gallons won’t be enough swimming space for them.

Is A 20 Gallon Tank Big Enough For 2 Goldfish?

20 Gallons is big enough for two small goldfish. However, as they begin to mature, you’ll need to get a bigger tank. As a rule of thumb, you should have 20 gallons for the first goldfish, and 10 gallons for each additional fish.

How Long Should A 20 Gallon Tank Run Before Adding Fish?

A 20-gallon tank needs to be cycled for 3 to 6 weeks before adding fish. Cycling is the process of establishing beneficial bacteria that break down ammonia and nitrite, which are harmful to fish. During cycling, do not add any fish to the tank.

What Are The Most Unique Fish For A 20 Gallon Tank?

You should consider adding Dwarf Puffers, African Butterflyfish, and Scarlet Badis to your 20-gallon tank. These fish have unique characteristics and behaviors that will make them stand out from the other fish in your tank, creating an interesting and one-of-a-kind aquatic community.

What Are The Coolest Fish For A 20 Gallon Tank?

If you want a cool and captivating aquarium, consider getting Betta Fish, Neon Tetras, Honey Gouramis, and Pygmy Corydoras. These fish have vibrant colors, interesting behaviors, and unique adaptations that will make your 20-gallon tank look amazing.

How Many Fish Can You Keep In A 20 Gallon Tank?

A 20-gallon fish tank can hold up to 15-16 small fish, but the exact number depends on the type, size, and behavior of the fish. It’s important to consider the fish’s comfort, water quality, and overall well-being when determining stocking levels.

Conclusion

From the dazzling colors of tetras to the playfulness of corydoras, each fish you choose adds its unique charm to your tank. Remember, it’s not just about setting up a 20-gallon tank – it’s about creating a home for your aquatic friends, where they can thrive, splash, and shine. 

Now you know all the best fish for a 20 gallon tank, which ones are you going to choose for your tank?

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