OK, I experienced this before withe my zoo's and a green star. When I first started feeding (using beneReef) and spot fed those corals they would close for 3 or 4 days before they opened again. After that I left those out off the feed list. Broadcast feeding affected them a little but nor much. The last 2 months or so my corals have been a bit droopy and not growing. My LFS recommended feeding some aminos. That worked great, within 48 hours after the first feeding, everything started looking better. I used "fuel" by aquavitro. My only exception was my sun coral. It has been doing great, growing best of any of my corals and was getting fed nightly. It would open about 30 minutes to an hour after the nightly fish feeding. I've been feeding it LPS food the same as i do the other LPSs. I dosed the aminos for the first time 8 days ago. Since then the sun has been closed up tighter than a drum (same as my zoas back when I spot fed them once). Has anybody else run into this? Starting to get worried about the guy. He's one of my favorites. All my numbers are good and haven't changed anything outside of dosing the aminos.