I do bi-weekly 50% waterchanges on my native tanks using my dechlorinated tap water, exactly the same as on my tropical community tank. Most of my fish are captive bred, but I'm currently keeping a group of hook and line caught northern longear sunfish that are thriving after 1.5 months of being in a tank.
I've seen sunfish, bass and gar living in small, stagnant drainage ditches and ponds that I would have never thought could actually support fish. The pond where I caught my sunfish was a small, scummy pool of water on my friends property, so in reality my water is probably much cleaner than where they were captured. Unless you're going to be keeping fish like trout or something similarly sensitive, you can probably do WC's as you'd do on any normal tank.