A couple of years ago I forgot to turn the filter and heater back on after a water change. I discovered my mistake 24 hours later. Naturally I panicked and tested the tank water to find zero ammonia and nitrite. Either it was the plants that took up all the ammonia made by the fish during that 24 hours, or there are 'filter' bacteria all over the tank with only a few in the media. Whichever it is, my QT still won't process nitrite fully after a month with mature media.
Hi
@Sue In an established tank, I have read scientific papers that talk about another type of microorganism that establishes itself and, if I remember rightly, takes over from the nitrifying bacteria. These are known as Archaea. I will see what papers I have on these. Having said that, I suspect that the plants were absorbing ammonia, nitrite and nitrate. I know people who rely entirely on plants to 'cycle' their tanks. This is all highly complex stuff but I try to understand it as best I'm able.
As for your QT getting stuck on nitrite oxidation, a few thoughts/questions come to mind:
1 Are you able to measure the phosphate level in your QT? I wrote up some notes last year as an aide memoire for myself to remind me to check some parameters when cycling a tank. I wrote it using RO water as a starting point. But, much of it is relevant when using tap water. I noted that phosphate needed to be maintained at a minimum of 0.2 mg/litre particularly during the breakdown of nitrite. It's all to do with phosphorus being part of something called ATP, which is "often referred to as the "molecular unit of currency" of intracellular energy transfer" (according to Wikipedia).
2 Do you have plenty of aeration in the QT?
3 Most nitrifying bacteria work best at pH 7.4 - 8.0.
4 Optimum temperature is 25 - 30C. I prefer this higher figure.
5 Ensure that nitrifying bacteria are not exposed to light.
That'll do for the moment!
JPC