i have a lot forming in my 2 month old tank. it started as pink dots on the glass, then it has spread out and the centers are getting darker. also, all of my base rock is now covered in pink/purple spots. i dose with calcium once a week between pwc's. i use only two capfulls at a time, but it seems to be doing some good. also, i only buy lr that comes from mature tanks that get broken down buy lfs customers when they move or whatever has motivated them to break down their tanks. i think this has helped tremendously, as i had almost no cycle during my initial setup. within 2 months i have loaded my tank with sps, polyps, mushrooms, royal gramma, marine beta, yellow wrasse, and citron goby, without a single loss. KNOCK ON WOOD!! i have NEVER seen a spike in ammonia or nitrate/nitrite(s). it would appear that mature lr is the way too go, at least it worked for me.