Hi all, I have been working at a lfs over the last year and some change and I’ve seen a decline in their Sps coral flats. I’ve kept heavy mixed reefs and had success with high end sps before but now I will be taking over the responsibility of these huge systems which I’ve only had under 50 gallon tanks before. I understand quite a lot about reefs but this still confuses me. Attached I have included our past water tests, live rock section which holds the bacteria for the tank (which I think is way too little), and some examples of the discoloring or dying corals. Personally I believe it’s a lack of live bacteria populations, higher nitrates (I’m a believer in low nitrate <5ppm systems), low alk, and lack of broadcast feeding. Currently we’re doing 80 gallon water changes weekly on this ~350 gallon system. No coral foods, mysis fed everyday. Any ideas will help! Thanks in advance.