as with any tank moniter your nitrates and if they get to toxic levels do small water changes to bring it down .. if you don't you could kill off everything. Also there is a point that if the nitrate gets so high it will hinder in the growth of backteria and you will get a stalled cycle.
I would recomend doing a 3 to 5 gal water change in a 15 gal tank any time your nitrate goes over 40 ppm, but that is just my opinion.. others might disagree.
Oh, and turn your lights on

if you leave them off nothing that came in that needs light will survive.
Steve
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*everything said above is just my opinion, and may or may not reflect the views of this BBS, its Operators, and its Members. If cornered on any “opinion” I post I will totally deny having ever said this in a Court of Law…Unless I am the right one*
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