I'm really frustrated... The phosphate level in my tank is 5ppm. I have been doing bi-weekly water changes (about 15 gallons) in my 90 gallon reef tank. My ammonia, nitrite, and nitrate are 0ppm. The pH is 8.2. I just changed out my PC's. My hammer and plate coral look like crap. My mushrooms, star polyps, and some other soft coral are thriving. They are even spreading. I have a bubble tip and sebea anenome that are doing fine. My yellow tang, pacific blue tang, yellow anthia, green manderine and tomato clown are fine. I am assuming that the high phosphate level is affecting my hammer and plate coral. They seemed to go down hill around the same time. I am feeding the fish brine shrimp and the coral phytoplankton. Is there anything else I should be adding to make the coral better? Any advice would be appreciated.