I have two, one on the SH tank and one on the 90g. I did have nitrate problems, and SHs are very messy. My nitrates are 0 on both tanks. I also do my water changes, although I did not at first to test the Aquaripure...it did bring my nitrates to 0 without water changes, so It does what it claims to do....but if you don't have a nitrate problem why spend the money.