I bought a 20g from petco. I am putting it in my daughters room. The tanks are drillable. After i took these pics i installed the bulkheads. Not thinking i pushed a piece of pvc into the bulkhead and i did not back up the bulkhead with pressure and CRACK. So be very careful when jacking around with the bulkheads after you drill the hole. Also drilling glass is so easy. All the hype about drilling glass is a bunch of mumbo jumbo. You dont need a special guide, you dont need anti-freeze, you dont need plumbers putty to make a little dam, and it does not take 10 mins to drill a hole. Just put a water hose on the back of the tank and have a steady stream of water flowing over where your gonna drill. Then angle the bit at a 45 degree angle so it doesnt ice skate. Once you got a good groove you can straighten out the drill. Just use the weight of the drill and dont push. Use a moderate speed. Not to fast and not to slow. Once you get almost through you wanna lighten up pressure on the drill. Put a sponge on the inside of the tank to catch the piece of glass.