Ideal Neon Tetra pH Level (& How To Adjust It)

Many aquarium owners love to put neon tetra fish in their tanks. These eye-catching fish are known for their vivid red and blue stripes and well-loved for their friendly nature. Since these fish get along so well with other non-aggressive fish, they are a happy addition to any aquarium. However, Neon Tetra pH needs to be a priority so these fish can be both happy and healthy.

One thing that many aquarium owners need to pay attention to is the water quality level. There are many aspects that need to be considered when creating a comfortable environment for your Neon Tetra fish. Getting the water quality levels right is one of the most important things you need to consider in order for these fish to thrive.

What Is The Ideal pH Level For Neon Tetras?

A Neon Tetra’s water conditions are very important, and aquarium owners need to do their best to recreate the fish’s natural environment. This may have you wondering what pH level your tank’s water needs to be at. The ideal pH level for their water is between 5.5 and 6.2.  With a pH level in this range, your fish will thrive.

What Happens If The pH Level Is Too High?

Neon Tetra are freshwater fish and the great thing about these fish is that they are highly adaptable to more acidic water. This means that many Neon Tetras are capable of living in water with a higher pH level. Some fish owners have successfully raised their Neon Tetras in more acidic water, with a pH level that goes above 7.

While it’s not ideal to keep your Neon Tetra in water with a higher than recommended pH level, it’s riskier to change their water’s pH level immediately than it is to let them live in more acidic water. Before we go over that, you may be wondering what happens if the Neon Tetra pH level is too high. This is what risks could occur:

Fertility Issues

There are many reasons why it’s important to recreate a Neon Tetra’s environment when you place them in a tank. Their overall health depends on it and so does their ability to reproduce. When the pH levels are too high, it will cause harm that will affect their reproductive process.

Many aquarium enthusiasts want to breed these beautiful fish, and if the pH level is too high, they won’t be able to.

Plant Problems

While Neon Tetra fish are friendly, they are also timid fish. There will be times when they feel stressed or anxious, and they will need a place where they can hide and have a timeout. Plants create the perfect resting spaces for your fish to mentally cool off and have a moment to themselves.

When the pH levels are too high, the acidity begins to harm the plants. The plants that are used to decorate a Neon Tetra’s tank don’t do well in more acidic water. Just like the Neon Tetras, their plants need consistent water conditions to stay healthy.

Kills Good Bacteria

Water that is too acidic can cause a lot of problems for the health of the Neon tetras. One of the main reasons why is because acidic water will kill all the good bacteria that these fish need to stay healthy. When the good bacteria are no longer present, it upends the aquarium’s nitrogen cycle. This could lead to many serious health issues for all fish present in the tank.

What Happens If The pH Level Is Too Low?

When the pH levels of the fish tank are too low, it’s not nearly as concerning as when they are too high. Keep in mind that when Neon Tetras are in the wild, they could be living in streams where the pH is as low as 4.0. The main thing you need to be concerned about with low pH levels is making sure there are no drastic changes.

While Neon Tetras are capable of surviving in a tank where the pH levels are slightly higher, they always do better when the levels are low. However, you’ll want to make sure the levels don’t get low too quickly or problems are likely to arise.


When the pH levels get too low, the Neon Tetra will likely feel very stressed. You may notice them spending more time alone or in their hiding spaces. In some cases, this may even lead to depression. Unfortunately, Neon Tetra fish will die easily if they are under stress.

Strange Behavior

Lowered pH levels could present various health issues to a Neon Tetra. They will be more susceptible to becoming ill. Many aquarium owners have noticed their fish are often restless when they become sick or are nearing death. They may even be swimming in a clumsy manner when they become ill.

How Can You Lower The pH Level For Neon Tetras?

When the pH levels are too high, it will create many problems for your Neon Tetra’s environment. However, one of the most important things to know about Neon Tetras is they can’t handle water changes very well at all. If they are living in a tank with a high pH level, you simply can’t place them in water with the correct levels.

While this may seem like the right thing to do, it could actually make the fish very sick. You will want to lower the pH level of the Neon Tetra’s tank so it has the ideal water conditions and will live a longer life. However, you’ll want to make sure this happens gradually. Here are a few things you can do to gradually bring that pH level down:

Aerate The Water

In order to bring down the pH levels, you will need to introduce air into the water. You can do this by simply leaving the water open in an unsealed container for a few days. This process will help introduce carbon dioxide to the water in order to lower those pH levels.

Add Plants

With bigger tanks, it may not be practical to leave the water out for several days. A great solution to bring the pH levels down is to add more live plants to the aquarium. Adding plants also gives you the option to inject CO2 into the tank. Another great (and natural) way to lower the pH is by adding driftwood in with the plants.

One of the easiest ways to bring down the pH level is by adding peat moss to the tank because it takes care of the bicarbonates in the tank’s water. Most Neon Tetra owners have had success from placing peat moss pellets or chunks throughout the tank.

How Can You Raise The pH Level For Neon Tetras?

On the other side of the scenario, you may notice that the pH levels are lower than ideal. When this happens, it’s likely because the water has been exposed to too much air or there is too much live decor for the tank’s space.

If this happens, you may increase the water’s pH level, but it’s very important that you remove the Neon Tetras first. Here is how you can safely increase the water’s pH levels:

Baking Soda

Once the fish have been removed from the aquarium, you can add baking soda to quickly reduce the pH level. Mix in 1 teaspoon of baking soda for every 5 gallons of water in the tank. It’s important that you give the baking soda at least half an hour to dissolve before putting the fish back in the tank.

Aquarium Salt

Aquarium salt is an easy way to increase the water’s pH balance, but it will also increase the water’s salinity. Since Neon Tetra fish can only tolerate a slight increase at a time, it’s crucial that you only add a small amount.

Other pH Level Increasing Items

There are many things that can be used to increase water’s pH level. The most important thing to consider is making sure you raise the pH levels gradually. Add any of the following items to your Neon Tetra’s tank to increase the water’s pH level:

  • Coral
  • Limestone
  • Texas holey rock

Final Thoughts: Everything You Need To Know About Neon Tetra PH

Neon Tetra fish are highly adaptable and can do well in nearly any pH condition. The main concern that aquarium owners should have about their fish’s water conditions is making sure it is steady. While Neon Tetras do best when their pH levels are between 5.5 and 6.2, they can still survive in higher or lower levels.

While Neon Tetra may be able to survive in pH levels that are out of their ideal range, they won’t thrive and are at a higher risk of getting sick. In some cases, they may even have reproduction issues.

To prevent these issues from arising, it’s important to make sure you have a suitable environment for your Neon Tetra. When you do increase or decrease the pH level, always do it gradually.

Leave a Comment