Ammonia And Nitrite

[FishyDan]

Now obviously we all know that a tank should have no Ammonia or Nitrite, but say a freak occurance happened and either Ammonia or Nitrite spiked after your cycle was complete, which would you prefer it was?

My question really is about the effect of both on fish and which is more deadly, im asking from a scientific stance.

 

[the Guru]

damage to the gills - impaired respiration - damage to skin, fins and the intestine... just about everything you could imagine realy.

IIRC nitrite is worse then ammonia, but neither is good at all.

 

[Corleone]

Ammonia is worse, but neither is good. Ammonia, as caused, messes up just about everything. It's usually noted for potentially permanent gill damage, but it can also cause black "burns" on fish's skin, among other things.

Nitrite binds to hemoglobin and reduces the blood's ability to carry oxygen. It doesn't cause any permanent direct damage, but it does cause suffocation.

Most of the ammonia you test for isn't toxic, but the toxic portion is toxic in amounts as little as 0.02 ppm. I believe all nitrite is toxic. There's a thread on the site for figuring out your toxic ammonia levels, but it doesn't get linked often, advice usually focuses on the fact that ammonia readings=cycle=bad regardless of toxicity levels.