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Aquarium Lab - Nitrite Test


What is nitrite?

Nitrite is produced by the beneficial bacteria in the aquarium and filters as they break down the harmful waste ammonia excreted by the fish. Although not as toxic as ammonia, nitrite is still very damaging to the health of the fish. Nitrite itself is broken down into nitrate which is virtually harmless to fish.

Why test for nitrite?

Any nitrite present in the aquarium will be very damaging to the health of the fish. Toxic nitrite can build up in aquariums where there are not sufficient beneficial filter bacteria to deal with the total waste from all the fish in the aquarium. This situation can commonly arise in new aquariums, when new fish are added, when the filter bacteria have been disrupted (e.g. during cleaning), or during accidental mis-dosing of aquarium medications.

What do I do if the Nitrite level is wrong?

If a level of 0.25 – 0.5 mg/l (ppm) is recorded then add NT Labs Aquarium Filter Starter. If a level above this is recorded then a substantial water change is essential. Change 25% of the aquarium volume for 1 mg/L (ppm) nitrite and 50% for nitrite levels above this. If any level of nitrite is detected NT Labs Aquarium Ammonia Remover will remove ammonia (and thus nitrite) from aquarium water and can be recharged. If you do record a nitrite level in your aquarium, then it is important to check other vital water quality parameters, especially pH and Ammonia.

To find out more about water quality and parameters in freshwater aquariums, click here.


  •  Q: Why do I run out of 1 reagent before the other(s)? A: We fill our test kit reagent bottles to a minimum amount before they are put through a vigorous QC regime. This means that the vast majority of bottles will in fact be overfilled by varying amounts meaning that the reagents may well run out at different rates but you should be able to carry out at least the number of tests stated on the packaging.

For common frequently asked questions, click here.



Available in the following variations:

Contains 80 Tests

Where to Buy?

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