What is the ideal water pH for betta fish?

In this article, we will answer the question “What is the ideal water pH for betta fish?”. We will also discuss how to achieve the most appropriate water pH for your betta fish.

What is the ideal water pH for betta fish?

Betta fish require a pH of 7.0 to thrive. They can, however, thrive in somewhat more acidic circumstances. The goal, much like with any fish, is to keep the pH stable rather than perfect. Your betta will thrive in an environment that is continuously overly acidic or alkaline, as opposed to one that is constantly altering.

What happens if I keep my betta fish in the wrong pH?

If you house any fish in a tank with an inappropriate pH, it will be a huge issue. A disease known as pH shock affects them regularly. This will usually kill them instantaneously, but it may take a little longer in other cases. The good news is that you still have an opportunity to correct the pH and save your betta if it does not kill them right away. You must correctly diagnose your betta before taking the required steps to preserve it. To do so, you will need to figure out whether they are experiencing symptoms as a result of a pH that is too low or too high. 

Even though you should test the pH of your betta tank regularly, it is still necessary to be aware of the signs of low and high pH. The following are some of the most prevalent signs of low pH in aquariums:

Symptoms of low pH in aquariums

Low pH in aquariums can manifest itself in a variety of ways. In your betta fish, not all of the symptoms will be obvious. Some of them will stand out among the other items in the tank. Plants, ornaments, and other tank mates are examples of items that can show some of the signs that your tank is with the wrong pH.


Burns or sores on your betta’s skin are one of the symptoms you may observe. When the water becomes excessively acidic, it will hurt your betta fish. You should check the pH of your tank if you notice burns or sores on its skin and are positive it isn’t suffering from another sickness.

Abnormal behaviour

You’ll also observe a lot of strange behaviour in bettas who are sick. They may, for example, be seen attempting to jump out of the water or swimming wildly. You will probably see them trying to breathe at the water surface. In more extreme situations, they can suffer from gills damages.

However, when using this symptom to diagnose a low pH in your betta tank, proceed with caution. It could also indicate the presence of contaminants in your tank or that your betta is sick. 

Low ammonia levels

Surprisingly, a more acidic atmosphere has the added benefit of lowering ammonia levels in the tank. Instead, there will be an increase in ammonium levels. Ammonium, unlike ammonia, is not hazardous to fish.

Symptoms of high pH in aquariums

There will be indications and symptoms of this, just as there will be when it is acidic. Some of the symptoms are very similar to acid environments. However, some are not.

Algae growth

A rapid bloom of algae development is one of the most telling indications of a high pH in your aquarium. If there is this rapid algae growth, it is recommended to check your water pH. However, too much light in your tank can also cause an increase in algae growth. 

So, in addition to algae growth, you should check for additional signs and symptoms.

More diseases

In the case your betta fish lives in a communal tank, it could also develop diseases with other fish. In tanks with high alkaline content, diseases like ich are more prone to occur. If you discover ich signs in your betta, you should test the tank water as well as treat your betta very away. 

Abnormal behaviour

If your betta has alkalosis, you will notice that it swims erratically and chaotically (a tell-tale sign of illness). In order to protect their skin from the alkaline, they may scratch themselves on ornaments or attempt to jump out of the tank. 

Your betta’s fins will also be extended wide apart, and abundant mucus will be released from the gills. This extra mucus is an attempt to protect his gills from the high alkaline water. 

Of course, testing your tank’s water with a pH tester is the best method to tell for sure whether it’s too acidic or alkaline.

How to modify the pH in your betta fish tank?

If the pH in your tank has been measured and found to be too high or too low, the next step is to adjust it. However, whether your betta tank’s pH level is too high or too low will determine how you modify it. 

Naturally altering the pH levels 

Your tank’s levels can be raised and lowered naturally. The benefit is that it will be less expensive, and no chemicals will be put into your tank.

pH levels can be naturally lowered in the following ways: 

Driftwood, peat moss, and Indian almond leaves are all good choices for this project. Just make sure you properly prepare them first! 

When employing any of these products, keep in mind that they should not be grouped. Spread them out to allow the pH to drop more quickly. You may raise the pH in your tank in the same manner you can reduce it.

Naturally raising pH levels:

To organically raise the pH levels in your tank, you’ll need to use a variety of ornaments. 

Coral sand is one of the nicest things you can utilize. Coral sand will gradually raise the alkalinity of your tank by releasing calcium into it. Other calcium-rich rocks, such as limestone or tufa, can be used in place of coral sand. 

Cleaning the tank

This is something you should be doing anyway. Cleaning your tank on a regular basis is one of the most effective strategies to maintain a stable pH.

Specifically, the water must be changed and the gravel must be cleaned. When you do this, you will get rid of everything that could make the water more acidic or alkaline, such as excrement, rotten food, and so on. 

You should also clean any algae from the sides of your tank and any decorations, and make sure the filter is clean.

Remove dead fish and plants

This should go without saying, but if you see something dead in your tank, remove it right away. Anything that decomposes in your tank will raise the ammonia levels, which will raise the pH of your tank.

Get a reverse osmosis filter

This is the most expensive option, and it is not usually required for smaller tanks. If you have the funds, though, it is well worth the expenditure because it will keep the water extremely clean. 

Reverse osmosis filters function by passing all of the water through them and filtering out any contaminants. 

They come in various sizes, with the larger size indicating a more powerful filter.

Try aerating the water more

Another excellent method is to ensure that your water is aerated. The more oxygen you can add to your tank over time, the more stable the pH becomes. It also doesn’t have to be a difficult technique. You can solve this by adding an air pump to your tank.


In this article, we answered the question “What is the ideal water pH for betta fish?”. We also discussed how to achieve the most appropriate water pH for your betta fish.

If you have any thoughts or doubts, feel free to drop us a comment below!

Frequently Asked Questions (FAQs): What is the ideal water pH for betta fish?

Can a low pH level kill a betta fish?

Unfortunately, low pH levels can quickly kill your betta fish. Depending on the size of the oscillation, your pet may die immediately or after a while. In any event, it is critical to maintain track of all water parameters and respond as soon as possible if they deviate from the norm.

Can betta fish live at low pH?

Betta fish thrive best in a pH range of 7.0-7.5. They can tolerate slightly acidic water with a pH as low as 6.5.

What may provoke an increase in pH in a betta fish tank?

The pH of your water can be raised by certain stones and boulders. Limestone and other calcium-rich minerals dissolve in the water, increasing the pH. In the case you need to increase your tank pH levels, you can opt for adding some shells or crushed stones to the bottom of your tank.

How do I lower the pH in my aquarium naturally?

Natural Driftwood will reduce the pH of your aquarium without harming it. Driftwood, like Peat Moss, releases tannins into your tank’s water, lowering the pH. It will, however, turn your water yellow/brown due to the tannins in it.

Do plants lower pH in aquarium?

Aquarium plants can change the pH of the aquarium, either boosting or lowering it depending on the situation.


Fabian. 2021. What is the Best pH Level for Betta Fish? https://www.aquariumnexus.com/best-water-ph-betta-fish/

Betta pH: The Correct Range Level. https://bettasource.com/betta-ph/

Billingsley, B. 2022. Ideal pH Level for Betta Fish (and How to Achieve it). https://www.itsafishthing.com/ideal-ph-level-for-betta-fish/

Ideal pH Level For Betta Fish (And How To Get It). https://www.bettacarefishguide.com/ideal-ph-level-for-betta-fish/