i see problems with that, the once a year water changes? your levels will get very high and you'll lose allot of fish, i would recommend like once every two weeks
76-77 is a little cold i would have it 78-80
skimmer i would leave 24/7
why are you overfeeding?
salt gravity is good i think recomened for corals is 1.025-1.026
all of this is IMO
