Man, I have an oooold saltwater tank. Like, old. I downsized to a 30 galon when I moved house from a 60 gallon and 30 gallon refugium underneath. All the same rocks and coral. It moved cross country with me in 5 gallon buckets, heaters and bubblers in the trunk.
The other thing I did, and this was in 2011, was switch to 90W of led lighting from 500W of MH. Best decision ever, even with 2011 Cree technology. Corals are all happy, temps are never a problem in summer with 80F in the house.
Good luck with your tank. It can be tough, but rewarding. But once things are dialed in it's easy. Although my corals are all soft now, so slightly less demanding than the stony stuff, it practically runs itself with regular water changes. Although I do have some algae now, after adding a couple cleaner shrimp. I was down to hermit crabs, small snails and starfish for awhile.
My biggest problem is the bubble coral that is roughly 25% of the tank. It's like 15 years old.