Setting up my 150 gallon tank....question re: water changes

[mark]

My system volume is about 200g (with a 145g display), I'll change out 25g every 3-4 weeks.

Fish include a couple of tangs, a foxface, 3 clowns, 3 chromis two damsel and a 6-line wrasse in a moderately stocked mixed reef. I'm running a skimmer with a macro fuge and nitrates test at zero, total nuisance algae could fit in a teaspoon.

Sure larger or more frequent changes wouldn't hurt but I think my tank looks ok.