Hope this might help some of you that are looking for answers on how to drill or about to drill your glass tank that is running or a acrylic sump. Thanks to many of the members on here and many hours of looking things over on the net i decided to drill my tank. This is the equipment that I decided to go with (yes i know some of it is to large for my tank planning for the future ;D). List of equipment: CPR CY294 cyclone bio filter with 2 built in 6" skimmers powered by 2 Rio 1700 pumps. Rated up to 500gals, max flow rate 1500gph, 26"x12.75x18" in dimensions. For all my skimming needs CPR AQUATIC, INC - Cyclone Bio-Filters LFS had a STEAL of a deal on this when i picked it up MSRP $899.99 bought it for $160 Next is the 30gal Sump found a great deal on ebay picked it up for $50 dollars. Then is the amazing overflow from glass-hole.com, Looks like very good quality work to me and with the overflow kit you get everything you need to fit your overflow to your tank. Nice fast shipping. Also you get candy lol Parts and pieces for the plumbing. Since I am planning to go bigger in the future I picked up a pump that will move some water. Picked it up from a member on here for the same price as a mag 9.5. I also picked up 2 return kits from glass-holes that were 3/4 returns with a "Y" splitter so I could disburse the flow coming back into the tank. In the return kit they include one 3/4" bulkhead a 3/4 adapter and loc-line connector with one 90 elbow. (will post pictures after my cam recharges) Finally down to the drilling. (first attempt in drilling a tank ever) I figured that I would drill my sump/fuge first to get a feel for how the bit works and all. When I ordered my bulkheads I didn't want to buy all different sizes of hole saws so i ordered 1 1/2 bulk heads for everything. So the most important part to ensure there is a nice round patter to follow when drilling I used the patter that I received in my overflow kit and marked my sump with a permanent black marker. Now to begin the drilling, the many vids i watched everyone started at a angle to get started so I did the same thing. To ensure they bit didnt "walk on me. (light pressure here is the key) After about 2 mins with (almost no pressure at all) there is a complete groove to follow. From there the only thing left to do was add some water here and there and hold the drill. Until this popped out the bottom. After a little cleaning and washing all the acrylic off, I fitted the bulkhead inside the hole. Fits just like it was made for it. That is all i have for now but stay tuned as i will be drilling my tank very very soon. My tank as it sets now. The overflow will be going in the center and the returns one on each side. Enjoy, I welcome any questions comments or other useful tips. thank you everyone for your help and support.