You could coat them with titebond as an extra precaution, but keep in mind, titebond dries yellow. I went with clear acrylic nail polish because they were so small and a dollar for a bottle of nail polish was cheaper than a can of spray paint for the same purpose. If you cover them with krylon fusion clear, you'll be fine. I coated a couple dried shrooms with it in my white's tank.
My rain system ran (I disassembled it) off of a pond pump. When choosing a pump, I would recommend going bigger than you would expect. The more outlets you have, the more pressure. Try to figure out how many nozzles you will have, then talk to your hydro rep, they will set you straight. Expect to pay close to $60 or so for a pump.
Hope that helps!