Instructions
Know the optimal pH level for the fish you would like to add to your aquarium. Researching on the Internet or in books will help determine the pH range that works best for a specific species of fish. If you are adding this fish to an existing tank, you will need to make sure the pH range of the new fish overlaps or is the same as that of the existing fish.
Test the pH of your water. You can purchase pH test strips at pet stores, health food stores or on the Internet. Test your water to determine the current pH. If the pH is within the range it should be in, then you can simply test each time you clean or add water to your tank. If the pH is lower (more acidic) than it should be for your tropical fish, there are a number of things you can do to raise the pH.
Add crushed coral substrate to the tank. Coral will help raise the pH of the tank, making it more basic. It is important to start slowly and add the coral in small increments, because a drastic change in the pH level will shock, and most likely kill, your fish. Placing the coral in a small filter bag rather than adding it to the gravel makes it easy to remove the coral if the pH rises too quickly.
Maintain and test the tank routinely. Proper maintenance is imperative to maintaining the pH you worked so hard to attain. Remember to test the pH of the water each time you do a partial fill and clean the tank to ensure the water remains at the optimal pH level.
How to Keep the pH Level Up in a Tropical Fish Tank
A critical component of keeping fish alive in a tropical fish tank is the pH level of the water. This is a measure of how acidic or basic the water is. Pure water, free of minerals and contaminants, has a pH of 7, meaning it is neutral. The pH scale ranges from 1 to 14. Any number below 7 is considered acidic and any number above 7 is basic. While literature may claim that a fish species thrives at a specific pH, they will usually survive in a range of pH levels, so as long as you are close to the optimal level and maintain the pH, your fish should be fine. A pH level below 6 slows the nitrogen cycle in the tank, which could be deadly to your fish.