I’m running a 46 bowfront. 6 month’s old with a pair of Oci, a Royal Gramma, Banggai, and tiny still see through tiger blenny. And while I hadn’t planned to go reef so soon, kept getting corals essentially given to me by local reefers making room for new corals. Big Colt, bunch of ricordea, bunch of mushrooms, gsp, Xenia, frogspawn, and bunch of different zoos. No room for a sump, and yet to find a reasonably priced hob skimmer (just heard of one rated for 75g I might get for 160 CAD so crossed fingers). Using my canister from when ran freshwater. Water running crystal clear (weekly clean light algae on glass bc forced to use tap water). Ammonia and Nitrates negligible. pH 8.2, and phosphates between lowest 2 colours on API kit. Alkalinity 10. Monthly ~20% water changes, and clean my canister at same time. Yet to have a problem. After reading horror stories about nitrate factories I had been cleaning canister weekly, but physical filters were barely dirty so moved back to monthly and still fine. Running ceramic rings, purigen, carbon, and phosguard. Going to remove the rings and add GFO ASAP.