Quote Originally Posted by ScorpiNO View Post
Feeding WAY too much.
Yup.

I'm guessing that you may also have an O2 level problem. Make sure you have plenty of surface movement. Do some large water changes - hard to do with that size tank - but that will help your nitrates too.

Feed nori to your tangs/angels once a day - only what they will eat right away. Soak it first, if you can. That will remove some of the phosphates.

Feed food only once per day.