Like 6 months now but I added a sump system with a refugium and my water is near perfect. I did a 5 gallon water change 2 weeks ago. 75 with a couple pieces of coral and 4 fish and 1 shrimp. Snails and crabs to
To me it is important to balance out the tank so water changes are not needed.
Besides water changes will limit but not correct changes in the tank's environment. So nitrates will still rise and calcium will still drop for instance.