numpty question

[andym127]

Hi, asking for a bit of advice. I've set up a new tankjust over a week ago, I have a layered substrate, co2 etc. and a few fish and a dosed once with TNC complete.

My question is, is there anything in a planted tank that can produce nitrite other than the nitrifying bacteria breaking down ammonia?

I started testing for ammonia a few days after setup and its always been zero. Then, almost just for fun I tested for nitrite and there it was, quite a bit.

I'm just struggling with the cycle happening that quickly and wondering if there's anything else going on.

Any thoughts?

[Carylnz]

Not a numpty question at all.
I can't help as I have never used CO2 but believe that may have something to do with it.
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