No water changes here...for about 2 years...Nitrates less that 2ppm, PO4 ranges from 2-10.
I feed frozen once a day(3 cubes), I have 12 fish including angels and tangs, and a monster cleanup crew. Refugium does quite well...dose aminos and trace bi-weekly. I'm not an acropora king by any means, but all other SPS does very well. My acros have suffered bacause of the mojanos that have moved in to my tank.