Currently my nitrates are around 20. I had live rock rubble in my fuge and it was collecting a bunch of crap. So I removed it all, so now there is only chaeto and a light back there. I am hoping that they will come down now. Honestly when I had 3 fish in my tank, even though they are all pretty small now it looked crowded and cramped. Fish were running into each other. I think 2 is max in a Biocube 14, unless of course you are going with much smaller fish. My .02