my tank has been up and running more or less since May (the filter has been at least, everything else got thuroughly rinsed in late july/early august). it is 29 gal, moderately/lightly planted (a few java ferns, two wisteria, and clump of water sprite), has a common pleco, 2 swordtails, and 9 tiger barbs. weekly water changes, about 25%. for a while now, my nitrates have been rather high, probably around 20, though closer to forty last friday before my water change. i also had ammonia and nitrite readings for the first time in a long time (months?) last week (nitrites the week before), but those are back to 0.
is there something i can/should do other than water changes that would help keep my nitrates low? the plants don't seem to be doing much, i don't over feed too often (it happens occasionally) and only feed 5 days a week anyway. and i don't think i'm overstocked enough to make this much of a difference.
unfortunately, i have to buy water for my tank, so i would rather not have to do more/larger water changes long term. i know i have to do more for now, but i'm looking for other suggestions at this point.