Pstanley,
Good questions.
There are canopys make specifically for PC lights; as well as MH and VHO. Actually, the "standard" canopy is only for NO bulbs.
There are retro-fit kits available for converting an NO fixture to PC, etc.. Buying on-line is often less expensive than buying from an lfs. There lots of on-line sources. I bought my MH/VHO canopy from reeffanatic.com. There's hellolights.com, aquariumlighting.com, and marinelights.com to name a few. If you do a search on this board on "lighting" or "PC" you should find lots of information.
Some canopies, like mine, do come with a glass or acrylic cover for the bulbs. Some will not. The object, though, in all cases is to keep the bulbs and fixtures dry. Water and electricity don't mix. Suspended light fixtures offer another alternative.
Jim
