Nitrates nor phospate readings are really bad. The only problem is that you do not know how much of these chems/compounds are being used by the problem algae therefore you don't really know what to do or what is causeing them. Just an example so everyone understands what i am saying.....You can have a problem with cyano and have a reading of 0 phos. this would be because the cyano was eating the phosphates faster than they where produced. I would not look at you test as some kind of golden key but more as a general window inside your tank. Especially when you are haveing a problem!