Female Telamonia DimidlataAs detailed in my last post, we are currently supposed to be going through the nitrogen cycle. The expected pattern is that

  1. Ammonia levels will rise and then the ammonia-eating bacteria will come along and turn it all into nitrites, at which point ammonia levels will drop off to zero.
  2. As ammonia levels are dropping, nitrite levels will start rising, until the nitrite-eating bacteria come along and turn it all into nitrates, at which the nitrite levels will also drop off to zero.
  3. As the nitrite levels drop off to zero and the cycle becomes established, nitrate levels will rise to the point where water changes become essential.

It should not, therefore, be possible for nitrite levels to rise unless there has been a previous spike in ammonia levels to get the ammonia-eating bacteria setting up home in the tank. Yet this is exactly what seems to be happening in my tank. Ammonia levels have been consistently nil, but I just measured nitrites expecting to confirm that they too were still nil, and they have gone up from nil to 0.8mg/l. What?! Where does the nitrite come from, if not from the ammonia? If there has been no ammonia, where does the nitrite come from?

PS Also, the water is yellowish and cloudy, possibly due to continued discoloration from the bogwood, but maybe not?!

Confused. Must ring fish expert tomorrow.

UPDATE: Amazing!!!!!!
(enough !!!!s for you?)

I just did a water change, replacing about 15% with fresh (dechlorinated) water. The effect on my fish was INSTANTANEOUS. I don’t know whether it was the sudden drop of temperature, a sudden rise in oxygen levels as a result of pouring in the new water, or a sudden dilution of the nitrite levels. Or what. But they have gone from quietly hiding in the weeds, with one of them ocasionally venturing out to sit on the gravel by the bogwood, to positively whizzing about the tank, playful as anything. Even the very quiet Sugar, who must obviously have been suffering a bit more than Spice, has come out to play. It’s ASTONISHING.

(enough capitalisation for you?)

I’ve redone my tests as well. The Nitrite is still showing the 0.8mg/l colour, but is lighter and closer to the 0.3mg/l border whereas before it was dark and if anything a bit closer to the 1.6mg/l. Anyhow, something must be better because the fish have almost literally *come alive*. Ammonia still nil, although on the retest I fancy the colour is closer to the 0.25mg/l borderline.

UPDATE: Explanation?

While dechlorinating my water for the water change I noticed that my dechlorinator is “Bioactive” (Interpret’s Bioactive Tapsafe). Apparently it adds good bugs. Maybe this explains why I had no ammonia spike, if the ammonia-eating bacteria were added to my water with the dechlorinator? I hadn’t set much store by this, as I’d read a few times that these bacteria-adding products are a bit over-hyped, what with the tricky task of keeping these cultured bacteria alive even without giving them ammonia to eat. But maybe this is the reason?

If my ammonia-eaters were at highish levels to start with, then it might well follow that they have been producing nitrite for a few days now, which explains why my fish were becoming increasing reclusive – they have been suffering nitrite stress.

I just can’t get over how happy my fish are! And if this bioactive stuff really has managed to accelerate tank cycling from 3-8 weeks to the point where on day 6 we are already well into the nitrite phase – then yay!