the rock says....
phosphates are always a problem in any form, are you using a protein skimmer? what kind of top off and water change water are you using? using RO or distilled water will help to lower your phosphates, as well as lowering the amount you are feeding your fish, if you have any, as well as a protein skimmer. you say your conditions are good, but i don't know what that means? any level of phosphate in your tank is a bad thing. i'd still like for you to give me an exact reading of your nitrates, telling me they are good may mean something different to you, a person that is testing it, or me. lemme know