Just a quick question to see if anyone knows. Params: Phos: 0 Nitrate: 0 Cal: 500 Mag: 1350 SG: 1.026 PH: 8.2 KH: 9.5 Stock: No fish, No CUC No sand. SPS and LPS w/ zoanthids and a leather Equip: LED lights, skimmer w mag drive 7 and kent venturi, HOB ref (3 gal) w cheato and a gorg, Hydor evolution 750 in the ref, WP 25 in main display. Display = 40g. Ok. Onto the question. When I set up my reef I used live rock that had been soaking in a dead system for about 3 months. About 50lbs. I boiled all but 5lbs (given to me at a later date) twice for 3 hours, srubbed with a wire brush and rinsed once and bleached in the sun for 3 months before constructing my reef ridge with acrylic rods and PC-7 epoxy. I had a horrible 6 month cycle. Cloudy water, then Bright green water, then diatoms ect ect. Well here it is 1 year after the cycle and I have dino on the surface of my LR. Just small patches and it never grows anywhere but the surface of the live rock. I've also got cotton candy popping up. The tests always say 0 for phos and nitrate. I don't feed. I tried purigen and for 6 months it never changed color. My cheato barely grows. My question is: Could the rocks be leaching old trapped phos at a slow rate and the dino consuming it before it can even get into the water column? I mean I just cant understand what is happening here. My SPS corals are doing AWESOME, my leather hasn't grown at all but opens up and looks beautiful. The frog spawn is healthy but never fully expands and the zoas just don't grow. Anyone have anything similar ever happen? I should have started with new rock, but even then you don't know if phosphate is trapped inside. Ugh. Also, I just did a 75% WC last week and the cotton candy is loving it. I normally do a 10% every month with reef crystals salt.