Ok, I have a 44 gal corner tank, mostly fake plants, sand bottom, couple very small java fern and a little bit of moss a buddy of mine gave me. Stocked w/ 2 quarter size angels, 4 zebra danios, 3 sm. aust. ranibows, and and a very small bushy nose pleco. Tanks been up about 4months. Ammonia went up, nitrites went up, ammonia came down, nitrites stayed up, nitrates went up, nitrates came down. Normal except my nitrites never came down. I do a 30% or so water change at least once a week. I've cut my feedings back to every other day last week, done 2 water changes since then. It dropped to .5ppm and went right back up to 1.0ppm.  Any one else have ideas I can try or what's causing the prob.