High Nitrite Levels in an Aquarium

When you set up an aquarium at your home or office, your aim is to bring the beauty of nature into that space. But recreating an entire ecosystem in a small glass box is not easy, and there are many things that can go wrong. One of the most common problems new hobbyists encounter is a high nitrite level. This common contaminant can reduce the amount of oxygen in the water and even kill your fish, so if you suspect a problem, you need to check it out right away.

  1. Test Kits

    • Nitrite is not visible, so you need a good test kit to know how much of it is in your tank. You can buy these nitrite test kits, along with test kits for ammonia and other contaminants at a pet store that sells fish supplies. Read the instructions carefully since not all kits work the same way. Test the water on a regular basis and add additional filtration if you see the water quality drop.

    Cycling a New Tank

    • When you set up a new aquarium, that tank goes through a cycling process, sometimes referred to as "new tank syndrome." During this cycling process, the quality of the water can change rapidly from day to day, with nitrite and ammonia levels spiking and then falling back again. It is important to test the water regularly when setting up a new tank. It is also important to choose hardy species of fish, such as danios and white clouds, for the new tank. These species can withstand the changes in water quality that accompany a new aquarium.

    Proper Tank Load

    • An overloaded tank is one of the most common causes of high nitrite levels. Even the best filter cannot process fish waste if the tank is overloaded, so if your nitrite levels are constantly high, you should look at the population of the aquarium. Hobbyists often use a rule of thumb dictating one inch of fish per gallon of water, meaning that a 10-gallon tank should contain no more than 10 total inches of fish, i.e., two 2-inch guppies and two 3-inch barbs. Although this is not a hard-and-fast rule, it is good to aim for this kind of balance, especially if you see high nitrite levels in your tank.

    Water Changes

    • One of the best ways to keep your fish healthy is to do regular water changes. Replacing a quarter to a third of the water in your tank every few weeks helps to remove built-up contaminants, including nitrites, from the water. Before you do a water change, you should treat the water you plan to use to remove any chlorine. You can use a commercial product available at many pet stores, or you can purchase spring water. If you have a well, you can use water out of the tap.

      It is best to use a combination gravel cleaner and siphon to do your water changes. The gravel cleaner pulls built-up dirt out of the tank and removes it while the siphon removes the water. When a fourth to a third of the water has been removed, you can begin filling the tank back up with new water.