Nitrites were gone, now back, what's up?

[houdini56]

I'm in about the third week of a fishless cycle using ammonia. For the last two days my readings were 0 ammonia, 0 nitrite, and 5 ppm nitrAtes. I kept dosing ammonia to 1-2 after taking a.m. tests. I was feeling pretty excited that I might get to order fish soon. Now I see why it's suggested that you keep testing for a few days even after it appears to be cycled.

This morning my tests show 0 ammonia, 0.25-0.50 nitrites, and nitrAtes at 5 ppm. pH has stayed the same through all this at about 7.6 or a bit less.

I'm confused, what could have brought nitrites back into the picture? The only thing that is different is I have accumulated some mystery snails with my plants (sigh) and so yesterday morning I put a small piece of lettuce in a cup in the tank to bait some of the little buggers. Could a small
piece of lettuce affect nitrite readings?

Feedback, please! Do I keep dosing with ammonia as I have been? Anything else I should do? thanks in advance...

[Trillianne]

Is it possible you dosed slightly more ammonia the last time?

More ammonia would turn into more Nitrites. So you are at a point when Group A of your BB which converts Ammonia to Nitrite is a healthy colony, but your Group B that converts it further is not quite a large enough colony to keep up with the Nitrite coming in to get it all converted to Nitrates.

[houdini56]

I think I understand what you are saying (much to my surprise!)....I'm using the same measuring tool every time I dose ammonia so it should be pretty darn close each time.

My nitrAtes have never gone over 5 ppm in this whole process, though much of the cycling information I'm reading says people will end up with over 20 ppm by the end of their cycle. I do have hard water and a 6-7 plants in the tank already so maybe that is a factor.

Is there anything I can do to encourage the nitrAte level up, or is it just a tincture of time situation?

[imma24]

Agree - if you are being consistent in your ammonia dosing, you appear to have enough bacteria to convert a certain amount - if you dose 2ppm instead of 1ppm, that requires the bacterial growth to catch up.

[houdini56]

I get what you are saying but I still don't understand what is needed to increase my bacteria to that point where it can make the conversion...?

[mommy1]

How soon after dosing did you test? I usually suggest waiting at least a couple hours to give the bacteria time to do their job. If you did wait long enough all you can do is wait it out and keep dosing ammonia when needed to complete the cycle again.

[houdini56]

I test first thing each morning when I get in my office and after testing I dose the tank....so I'm testing 24 hours after dosing.

It looks like patience is in order once again.

[Trillianne]

Plants will consume some of the Nitrates that are produced. I'd not worry about trying to get that number higher, just after adding fish making sure you keep it down to an acceptable level.

Any rotting animal or vegetable matter would produce more ammonia.