Noob question:

[mike31154]

I vacuum the substrate a little on every water change. Doing a small area a little deeper and everything reachable lightly every time will help keep the crud level down without disturbing all the beneficial stuff too much.

While you're out shopping have a look at some of the hang on back (HOB) skimmers available. I've been running a 77 gal sumpless for close to 4 years and went from FOWLR at the start to where I now have anemones, soft and LPS corals. My skimmer came with the used system and is an old school DIY counter current, wooden air stone unit. With a few of my own mods, it works very well. If the skimmer prices are a little hard to take, search the net for DIY plans and if you're handy you should be able to get something built relatively easily for less money. Even with a FOWLR, once you see the stuff a skimmer can remove from the water over time, you'll be convinced it's a good thing for your livestock and to ease your maintenance burden.

Further on the subject of water changes, it's recommended to use RO/DI or distilled water to prepare your mix. Can depend on your source water too, but long term you'll have better results with pure water than with treated tap water when running a salt water system.