Don't worry about using water changes to 'catch up' the diatom algae (brown dusty stuff) will die off by itself as the tank ages. It's just part of the process. My tank was brown for about 3 weeks then almost overnight it disappeared on it's own. Just clean the front glass so you can see in! 
Mike
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55 gal FOWLR, SeaClone 150 skimmer. 2" LS, 50# LR. 29Gal sump/fuge ViaAqua 2600 pump, chaeto, 1" sand, LR
2 Percula Clowns, Scissortail Goby, Black Birdwrasse, Keyhole angel, Lawnmower Blenny, |