The glass is 5/8" tempered. The only lighting on those shots is the actual tank lighting. In a reef tank, you need LOTS of light. I have just over 400 watts of lighting over the tank. The bulbs are VHO (very high output fluorescent) and are designed to accurately reproduce the color spectrum (and color temp, around 10,000K) of sunlight.
Even with that much lighting, I usually have to really tweak the camera to get good shots. I have to shoot around 1/125s shutter speed, which is not nearly slow enough for that level of lighting. Consequently I usually end up with a LOT of dark shots, even by increasing the exposure and ISO settings in the camera. I'd say on average I'll shoot 50 shots of the tank and get 3 or 4 that are good, useable shots.
To keep glare down I shoot at night with the room lights off and the tank lights on. I use a tripod for shooting the sessile invertebrates (corals and such), but usually hand-hold to shoot the fish.