About Nitrites

Nitrites are one of the most harmful pollutants in aquarium water.

Nitrite is a toxic waste material found in varying concentrations in most aquariums. It is produced as nitrifying bacteria in the biological filter break down ammonia. As the biological filter develops and grows, the bacteria use nitrite as a food source, converting it to non-toxic nitrate, thus reducing the level of nitrite in the aquarium. Regular testing for nitrite is important because even low levels of nitrite affect the red blood cells of fish, reducing their ability to carry oxygen, thus causing suffocation and fish death.

During the startup of a new tank, nitrite levels will soar and can stress or even kill fish. However, even after an aquarium is initially “cycled,” it is not unusual for your tank to experience nitrite “spikes” from time to time. When you do your monthly testing, include nitrite testing as part of the routine. Any elevation of nitrite levels is a red flag that indicates a problem brewing in the tank. If a fish is ill or dies, it’s wise to test for nitrite to ensure that is not contributing to the problem. Use a Fritz Nitrite Test Kit to determine if there is nitrite in your aquarium. Nitrite levels should be at 0 ppm (parts per million).

If nitrite is present, take immediate steps to reduce it.

  • Always reduce feeding temporarily if any nitrite or ammonia is detected.
  • If the nitrite level is above 0.5 ppm, perform a small water change.
  • Remove as much waste from the bottom of the aquarium as possible.
  • Treat replacement water with FritzGuard® Water Conditioner with aloe vera and vitamin E to greatly reduce fish stress and the chance of infection.
  • For best results, add FritzZyme® 7 Freshwater Nitrifying Bacteria or FritzZyme® 9 Saltwater Nitrifying Bacteria to naturally reduce toxic ammonia and nitrite quickly.
  • Where available, add TurboStart® 700 or TurboStart® 900 for the most rapid and permanent ammonia/nitrite elimination possible. FritzZyme® TurboStart® is a safe and effective, super-concentrated nitrifying bacterial product.

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