How to safely raise pH in your fish tank?

Keeping your aquarium environment healthy and free of pollutants is very important. Your aquarium should have a stable pH. Before you start adjusting your pH, ask yourself if you really need to.

A majority of fish species have some tolerance to changes in their water parameters and it’s important to monitor your water. Most types of fish can be kept in a wide range of pH, although you need to make sure that there are no signs of distress.

While raising the pH of your aquarium requires a few precautions, you can do so with these safe methods.

Key Takeways:

• pH scale measures acidity (below 7.0) and alkalinity (above 7.0) of water.
• Most fish species tolerate a range of pH levels, but signs of distress indicate a need for adjustment.
• Low pH levels (below 6.5) are harmful to most fish and lack buffering capacity.
• Maintaining stable pH levels is essential for fish health; drastic changes can be harmful.
• Methods to rise pH include ater changes, bking soda, crushed coral or aragonite sand, chemical pH buffers, removal pH-lowering items.
• Avoid using store-bought chemicals to raise pH as they can cause rapid and harmful fluctuations.

What causes low pH in an aquarium?

First we’ll diagnose the cause of low pH aquarium water.

Wrong Maintenance

Aquariums have their own unique set of problems. Usually, the main culprit is poor water quality. 

As your fish waste and leftovers accumulate in the aquarium, they put off more and nitrate (NO3-) in the water. Nitrate is an acid, so as nitrate builds up in the water, the pH gets lower.

If you want to keep your aquarium clean and healthy, you should do routine maintenance each week, like adding water or cleaning out the gravel. To learn more about nitrate in the aquarium, check out this article.

What is the pH of your tap water?

I highly recommend that you check your tap water’s pH to make sure it’s neutral so you don’t develop any unwanted conditions in your fish tank. If your water has a good pH, you don’t need to do anything special to increase the pH of your aquarium. You just need to change the water.

You should perform 30-50% water changes at least every other day until the water in the tank has reached a good level. Later, you can make one water change per week to keep the water parameters in balance.

Tannins

This might sound strange, but another way to lose your balance is to have a decor that has an excess of tannins. These organic chemicals help the plants defend themselves against disease-causing organisms and are often present in wine and tea. 

These acids can drop the pH level and stain the water in the tank brownish in color. 

The most common sources of tannins in the aquarium are driftwood, alder cones and leaves (especially Indian Almond Leaves). Driftwood, alder cones and leaves releases tannins into the water, making it turn brown.

So if you notice that the water turns brown and pH is dropping you can guess your aquarium is high in tannins.

It is wise to boil driftwood to remove tannins before putting it into the aquarium. You can add salt to water (150 g of salt per 1 gallon of water). Boil it for at least 3 hours. The water will turn brown if it has a lot of tannins in the wood. If the water becomes very black after boiling, it’s time to discard it and boil again with fresh water. Continue doing this for as long as the water stays clear.

If you don’t want to spend hours and hours boiling your driftwood or it’s too big to put in the pot you can soak driftwood in salty water (150 g of salt per 1 gallon of water). This should clear most of the tannins and surely prevent it from affecting the water color. 

In some cases, brown water is desired by fish keepers. Driftwood doesn’t immediately lower the pH. However, it is often used in aquascape.

Poor oxygenation

Fish respiration releases carbon dioxide, which can drop the pH. There are many reasons to use a filter in your aquarium, and this is one of them.

The pH in an aquarium with an unfiltered tank can be very low because of lack of aeration. This is often the case in betta tanks. The most important thing is to make sure the water is always clean and not contaminated by any chemicals, so this can be achieved by using a filter.

You should always have at least one filter in your tank. The main purpose of a filter is to remove ammonia and nitrite from the water, but it also reduces the concentration of phosphates. Filters also helps with water circulation, which helps to keep the water moving and prevent stagnation. It allows better gas exchange and increases oxygen levels in the water.

An aquarium air pump with an air stone is another piece of equipment you can keep in your tank. A larger bubble size will create more surface area for gas exchange, which will lead to faster water movement and increased oxygenation.

If you boost the oxygen level in your water, it drives down the amount of CO2 and that lowers the pH.

Is low pH dangerous for fish?

Low pH levels are not good for your fish. But most importantly, what constitutes “low pH?”.

It means that your aquarium water has a pH that is lower than the optimum for most freshwater fish. Most fish aren’t very happy with the pH of water that’s lower than 6,5. In fact, there are many species of fish thrive in acidic water. However, we must remember that they have a certain range of tolerance. Low pH is much more dangerous for fish than high pH. 

If the pH level is under 6.5, then there is no buffering capacity to prevent the pH from plummeting further.

There is no need to add more chemicals or filter media if the pH of the water is slightly higher than the recommended range for your fish species. Fish are very tolerant of most conditions, as long as they’re well-acclimated to those conditions and the water parameters are kept steady. 

If you keep your water parameters stable, you are going to have a much happier fish population in your tank. I’m not saying it’s not possible to get that perfect pH, KH, or GH ammonia reading. However, you don’t have to strive for perfection just because you read it in an article. The reality of keeping a healthy and happy fish population in your aquarium is much easier than you may think.

When you read post about the ideal water parameters for fish tank, you must know that those numbers are basing on the conditions found in the natural habitat of fish.

Fish you see in the pet store have usually been tank raised for many generations and thus are well adapted to home aquariums.

As I wrote earlier, most fish will be able to adapt to the parameters in the tank.

Nitrogen cycling is important for keeping an aquarium clean, but it is not all that matters. You also need a stable temperature, optimal water chemistry, and routine maintenance to keeps your nitrates under 30ppm.

To be clear, you don’t need to increase the pH in your aquarium if your fish are doing well.

How To Raise Your Aquariums pH?

It’s possible to get into an accident while learning how to raise aquarium pH. In general, I don’t recommend the chemicals you see in stores. They can cause huge swings in your pH, and they will wear off pretty quickly.

Water Changes

Water changes are the best way to correct a gradual drop in pH. Regular partial water changes will also keep your tank happy and healthy.

For optimal results, it’s recommended that you make several small water changes over 24 hours rather than one big one. You should do 20-30% water changes every other day until the pH levels are back in. 

By avoiding rapid changes to the water’s pH you won’t cause any problems. In addition, if you vacuum your substrate often to remove uneaten food and fish waste, that will keep the pH of the aquarium stable.

Remember that high nitrate in your tank may dropping the pH. If you’ve already got the pH under control, the next step is to perform 50% water changes every week. These changes help remove nitrates, and they also help keep the tank cleaner.

Baking Soda

Sodium bicarbonate (baking soda) increases the KH and pH of water. Add 1 teaspoon of baking soda per 5 gallons of water. Dissolve 1 teaspoon of baking soda in some tank water. Then add it to your aquarium.

Don’t forget that most aquariums have other things in them, and they take up space and decrease the amount of water in the tank. An aquarium with substrate and decor has less gallons water than its full capacity. 

But, you will need to add baking soda periodically to maintain the PH level. It’s important to be careful how much baking soda you put into the tank at one time, because it could cause a sharp rise in the pH of your water. 

Add doses, then wait a few days before adding more. Changing your pH quickly may shock your fish and cause them to die. Make small changes over time. 

To keep your water at the right pH level, you’ll need to add the amount of baking soda every time you do a water change. Avoid putting too much baking soda into the tank at once because it might create a shock or spike that could kill your fish.

Add crushed coral or aragonite sand

If you want to raise the water pH naturally, you have to add some substrate, shell, or rockwork to your tank.  One type of substrate that’s often used by hobbyists who have African cichlids that prefer a relatively high pH is a crushed coral substrate. 

The main component of seashells, aragonite sand and crushed coral is calcium carbonate. The only difference is that crushed coral is in bigger chunks and aragonite is in very tiny little sand-like pieces.

There are many ways to add crushed coral or aragonite sand to your tank. 

Both of these ingredients are responsible for lowering the pH of the aquarium water. You can put crushed coral in a bag and use it in your filter.  Aragonite sand you can use as substrate in your tank. 

Both will increase the GH and the KH. If the KH increases, then the pH increases as well.

Aragonite sand or crushed coral substrate is my top choice for substrate with African cichlids. Over time, the minerals in the soil will rise the pH and make it more stable. The fish will adore digging around in the sand. 

Adding the sand will keep pH at the right level, but it doesn’t have to be added each and every time you do a water change.

Chemical pH Buffers

Using chemicals to control the pH level in aquariums has its risks. Many chemicals are toxic and can be harmful to your fish.

You should add more chemicals to the water every couple of weeks to maintain the effect. Generally, when other remedies have failed, chemical buffers can be used as a last resort.

Remove pH-lowering Items

It’s possible that you’ve unintentionally made your aquarium more acidic. By removing some of the things listed in “how to lower pH” section your pH may rise a little bit. 

If you added wood or Catappa leaves to your aquarium, you might not have realized that it would affect the pH.

To remedy the situation, you simply have to figure out what’s causing the pH to rise and remove it from the tank.

Frequently Asked Questions

Rise pH Infographic

In Conclusion

Every kind of fish prefers a specific pH that’s similar to the pH in its natural environment. But remember! There’s no need to try to achieve the perfect pH. Constantly adjusting the pH level of your aquarium water can kill your fish. Instead, try to keep the pH level of your aquarium within your fish’s tolerance zone.

Typically, the only thing you need to do to maintain a healthy pH is to make routine water changes. Rapid changes in pH can do more harm than good.

It’s better to keep your numbers steady and stable than to constantly go chasing after imaginary perfect numbers.

In order to maintain the right pH level for your fish tank, you’ll need to alter the pH using one of the chemical-free methods I’ve recommended.

Thanks for reading, and please comment with any thoughts you might have. Don’t forget to share this article to help others find this useful content.