I have a 75 gallon tank that about 1 day out of the week, the corals seem happy. Most of the time some of the corals like acans and Duncans don't look too hot. My tank is very clean, but just within the past 2 weeks, the coraline on my rocks have been turning white and there has been no new coraline growth. My corals are growing so slow, some haven't grown at all. I've had my acans for about 3-4 months now and not one new baby polyp. My KH is 9, Cal is 420, MAG 1320, SG 1.025, ph 7.8, I use a 150 reef octopus skimmer, I use RSCP salt and my lighting is 4 kessils, 2 ocean blue and 2 sky blue. I use RO water for to top offs and water changes. Just last month my frogspawn corals and coraline were growing well. Now everything just stopped growing. Any thoughts? This may sound crazy, but the only thing I can think of at the moment is, the Asian beatles have been waking up around my area. Just yesterday alone I pulled out about 10 dead beatles out of my tank during a water change.