Cardinal tetras are breathtakingly beautiful fish that are usually 1.5 inches in length. Their small size and active bodies help them adapt to a wide range of environmental factors. While cardinal tetras do not usually have problems with pH levels, over time, exposure to unstable pH can cause several health issues. The fish may even develop deformities and become a host to different diseases. For a safer experience, here’s everything you need to know about the cardinal tetra pH level. 

What Is The Ideal Cardinal Tetra pH Level? 

Cardinal tetras are known to be adaptable. They can easily adapt to various conditions. This fish species is also able to survive in various pH levels and water hardness levels. You should, however, try to provide these tetras with the most ideal pH level for the species.

Cardinal tetras can survive in acidic pH 2.9 and alkaline pH 8.8. However, the best pH level for a cardinal tetra is near neutral levels. Scientifically, it’s agreed that cardinal tetras prefer a pH level between 5.3 and 7.8. 

What Happens If The pH Level Is Too High? 

Cardinal tetras are generally able to survive in water that has a high pH level. This is due to their ability to adapt to many different situations. This does not mean you should not take care of a high pH level in the tank.  

When a cardinal tetra is exposed to water with high pH levels, it becomes more vulnerable to certain health problems. A high pH level will likely not be a direct cause of death in your fish. The health problems that develop due to a high pH level, however, can decrease the lifespan of your fish.  

A sudden increase in pH levels within the tank will also put your cardinal tetras under stress. When these fish are stressed, they also become more vulnerable to certain health problems. In turn, this may further decrease their general life expectancy.  

What Happens If The pH Level Is Too Low? 

Similar to a high pH level, cardinal tetras can live in a low pH tank, too. 

A low pH level is unlikely to kill your cardinal tetras. As noted above, they can survive on pH levels of even 2.9. Still, the gradual toxicity can cause them to become stressed. The stress that the cardinal tetras experience leads to health problems, and, in turn, they can die from these conditions.  

It is especially important to avoid a low pH level when the fish are young. They need an adequately balanced pH level to grow without any health problems. During this time, they cannot adapt to various conditions as well as a mature cardinal tetra. When the pH is too low for a young cardinal, there is a risk of serious health issues.  

How To Lower The pH Level In The Tank? 

When the pH level in your tank is too high, you risk the health of your cardinal tetra. Even though a high pH level may not kill the fish, there are health problems that will likely develop. With this in mind, it is important to learn how you can lower the pH level in your tank.  

There are a few ways to do this.  

Use Aerated Water 

If you use tap water, then you need to consider how soon you add the water to the tank. The pH level may be 8.5 or higher when you use regular tap water. In this case, the pH level is higher than what cardinal tetra can tolerate.  

Place the water in an open bucket for a few days before you add it to your tank. Make sure to test the water’s pH level every day. You will find that aerated water tends to experience a drop in pH level after standing for a few days.  

Once the aerated water reaches the right pH level, you can add it to your tank.  

There are other options that you can use. This can be useful if storage space is a bit limited around your house. In such a case, having a few open buckets of water around may not be a viable option for you.  

Add Some Live Plants To The Tank 

The use of live plants in the fish tank is a great option to consider. This helps to add to the aesthetics of the tank. Live plants are also healthy and a playful part of the tank, especially for cardinal tetras.  

Live plants have the ability to bring down the pH level of your tank’s water. Note that this does not apply to plants that are made from plastic.  

Use Chemicals To Reduce pH Level 

Another option is to use certain chemicals. There are a few chemical solutions that can be used to bring down the pH level of the water in your tank.  

Seachem Acid Buffer is a popular option that a lot of fish owners tend to use. Up to three drops of the chemical solution can be added to each gallon of water that you add to the tank. The number of drops used depends on how much you need the pH level to reduce.  

Other Options 

Apart from using aerated water, chemicals, and live plants, you can also try these strategies if you need to further reduce the pH levels: 

• Add some driftwood to your tank. This has been shown to cause a decline in pH levels.  
• Use CO2 injection if you have a planted aquarium.  
• Mix some RO/DI water with your tank’s water. You will need a RO/DI water system for this strategy.  

How To Raise The pH Level In The Tank? 

There are times when you will find the pH level of your tank is too low. In such a case, restoring the pH level to a more neutral rating will make the water safer for your cardinal tetras. A few strategies can be used to raise the pH level in the tank. The specific strategy depends on how much you need the pH level to increase.  

Use Baking Soda 

A lot of people find that baking soda can effectively increase the pH level of water. A single teaspoon should be added for every five gallons of water in the tank. You do need to ensure the fish are not in the water when you add the baking soda.  

Once you have added the baking soda, wait about an hour. Test the pH level of the water again. See if it has increased to the right level. Make sure it doesn’t rise too much, as this may cause the pH level to be too high in turn.  

When the pH level of the water reaches between 5.3 and 7.8, you can put your cardinal tetras in – as long as it is about an hour after you have added the last batch of baking soda.  

Add Some Seashells 

A surprising strategy to raise the pH level of water is to add a couple of seashells. There are carbonates in seashells that will dissolve in your tank’s water. These carbonates dissolve at a very slow rate, which means the use of this strategy is not an immediate solution for water with a low pH level.  

Instead, you can rely on the seashells strategy to raise the pH level of your tank over a longer period of time. Add up to two seashells to every one gallon of water that your tank contains. This will add enough of the carbonates to raise the pH level. At the same time, adding only one or two per gallon of water reduces the risk of increasing the pH level of the water too much.  

It is important to ensure you do not use seashells that have been made for decoration purposes around your home. These seashells are usually painted. They will also contain harmful chemicals. Adding these seashells to your tank will likely cause you to contaminate the entire tank. This can prove to be worse than an unbalanced pH and will most likely kill the cardinal tetra. 

Instead, visit a local pet shop. These stores will usually be able to offer you natural seashells that do not contain such harmful chemicals. In turn, you won’t do any harm to your cardinal tetras while increasing the pH level of the water.  

Recap 

Cardinal tetras can adapt to a range of pH conditions. However, the best one for them is near the neutral ranges. Make sure your cardinal tetras live in water, having a pH level between 5.3 and 7.8. A pH level that is too high or too low can cause problems with your cardinals. There are strategies to lower or increase the pH level if you find that the pH in your tank is not balanced.  

If you’re keeping other fish in your tank, then you need to make sure the temperature is right for them too! If you want to find out more, then here’s what you need to know about the pH levels for plecos, cory catfish, guppies, mollies, angelfish, and gouramis!