Well i've been persistent with weekly water changes. I just completed my last water change on Sunday and i don't feed them heavily. Keep in mind that they are juveniles. They are extremely small. Nitrates are at zero with an API test kit. I'll probably take some water to the LFS to see get another opinion. My tank is also a 90 gallon.

How inaccurate do you think the test kit can be if its giving me 0 nitrates?