I've just started a 10% weekly water change regimen. I had been a little inconsistent. One of our Local Stores has a 180 with very simple plumbing, no reactor, no refugium, small sump. He has amazing growth, polyp extension, and water quality. His secret: He does HUGE water changes 1-2x a week (30-60gallons) and doses B-Ionic. Obviously most of us don't have the time and cash it takes to burn that much salt mix and dosing supplements.
BUT, my point is, I've seen first had the benefits of a strict water change schedule. I'm a believer. I run a reactor, I dose Mg and Ca once a week and have been doing the 10% changes and definitely see an improvement! I figured the extra $$$ I've spent on supplements and other remedies outweighs the cost of a bucket of salt every 6 weeks.
Stick with it and you won't be sorry!!!
Best of Luck!