IMO, ….
….get the tank drilled if it’s not already.
-Run a sump with a skimmer over-rated for a 77g. Say a Euroreef CS6-1 or CS6-2 ,or an ASM G-2.
-Go with about 100lbs of Live Rock.
-Crabs, crabs, crabs….of the hitchhiker variety. Check with your LFS when they get LR shipments in. Usually some show their beady little eyes on arrival of the LR and can be had then. Crabs hide during the day and come out at night. Triggers hide during the night and come out by day. Perfect.
(Not sure about Blue-legged hermits. The ones I have in my Reeftank are always cruisin’ around by day….so maybe they can sense danger when it’s present, and hide by day if a Trigger is around. Don’t know).
-Good water circulation to help keep crud suspended in the water column.
-Water changes. At least 10% weekly.
-Understock for a lower bio-load.
Some other things to consider….
-Go Bare Bottom. Personally, I don’t like it but it certainly does allow for the option of vacuuming crud out.
-Utilize a de-nitrator such as Kent’s Nitrate Sponge.
-Run a refugium.
Maybe more ideas than what you’re looking for but it’d all help, IMO.
HTH and cheers
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