About three weeks ago I added my first sps corals to my tank. I've been taking things slow with the tank and it's already been up for over four months. In my previous tank I was quite successful with a pocillopora and a montipora so I'm not completely new to sps. But anyways, I got three acroporas and one millepora all from Aqua SD and when I received them they were all brightly colored for the most part and shower promising polyp extension after 24 hours in tank. For some reason, since pretty much day one, the four corals have been losing color and even bleaching. Here are my parameters: Temp: 77 Alk: 9 dKH Calcium: 450 ppm Magnesium: 1440 ppm Nitrates: 7 ppm (a little high I know) Phosphates: 0 ppm (have always been zero according to Hanna checker?) Flow is two mp10s running on reef crest mode at full power and lighting is a gen 1 radion with gen 3 clusters and TIR lenses. My first thought was that the light was too intense thus causing bleaching but the radion schedule maxes out on the 14k preset at 25% intensity so I doubt that's the issue. :\ The only other possibility that makes sense is that the corals are suffering from nutrient deprivation. If phosphates truly are zero or close to zero the zooxanthellae algae may be dying off. I turned off the media reactor that had some carbon and a few tablespoons of GFO in it to try and let the phosphates rise slightly. Also, two days ago I target fed each coral cyclopeeze and they reacted quite well in terms of actually capturing the food but if anything they looked worse the next day. I'll be ordering some reef chili from BRS and start feeding them that to see if that helps but I'm seriously worried that I'm missing something and the corals are really starting look rough. I don't want to lose them. The acropora in the middle was a fairly bright green when I got it and has shown the most uniform fading, the blue acropora is bleaching quite severely on the side of the base exposed to the lights, the pink acropora in the front left stopped extending its polyps about a week ago and within the last couple of days has showed some decay and algae growth on the tips, and the pink millepora in the back, though having lost the least color, was extremely fuzzy and had beautiful poly extension when I received it and has slowly shown less and less polyp extension. Any advice or explanation is much appreciated.