Hey Cubereefer, we have a 36x36x25 cube. Here's a few pics of how I did the stand and canopy. We originally had a sump under the tank in the stand, but eventually moved it to the basement. It was just to cramped under there for my liking. But the stand was designed to hold a sump underneath.

The canopy was designed to be able to get in the tank from all three sides. This might give you some ideas.

As far as the glass for the lights, if your running single ended bulbs you really don't need glass, and if your running double ended bulbs,most likely a glass shield came with your setup. In both those situations, the sheilding is built in.

Venting the chiller should be fine, provided the unit itself doesn't get hot enough to transfer to the tank. Never ran a chiller myself though.

Ballast can stay under the stand, but might want to put them up so if you do get a leak, they won't be sitting in water. Different types of ballasts put out different heat. If it does heat up the tank, they shouldn't be hard to relocate if needed.

Here are some pics of the stand and canopy for our cube.

IMG 3902Medium - Need suggestion on stand/canopy build
IMG 3901Medium - Need suggestion on stand/canopy build
IMG 3905Medium - Need suggestion on stand/canopy build
IMG 3903Medium - Need suggestion on stand/canopy build