water chemistry

Nitrite

NO2-

What does Nitrite mean?

Nitrite (NO2-) is the second product of the nitrogen cycle, produced by Nitrosomonas bacteria converting ammonia. Moderately toxic - causes brown blood disease at >0.5 ppm.

How is Nitrite used in aquariums?

Test weekly during cycling; target is 0 ppm long-term. If detected after a tank crash, do partial water changes + add Stability or similar bacterial supplement.

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Frequently asked questions

What does Nitrite mean in fishkeeping?

Nitrite (NO2-) is the second product of the nitrogen cycle, produced by Nitrosomonas bacteria converting ammonia. Moderately toxic - causes brown blood disease at >0.5 ppm. Test weekly during cycling; target is 0 ppm long-term. If detected after a tank crash, do partial water changes + add Stability or similar bacterial supplement.