I went to home depot and bought 1/4 inch plexi glass clear. I decided where my pumps would permanently go for best flow and measured everything very closely. I then drew all the pieces and sections that needed to be cut on the plexi glass. You can use cardboard first and then trace if it helps you better, but just make sure when you start to cut your plexi glass your pretty dead on cause I'd hate to see something like it not reaching from side to side. My cousin thought I used a dremel tool because everything was so smooth and precise but the truth is I didn't even think of that at the time DA. I used tools from my dewalt kit but don't want to mention which ones because unless you’re really good, and you might be, I would feel bad if you took a finger out. I think the dremel tool would work the best and safest if it was to be done again. OK I picked 1/4 inch which is pretty thick cause of 2 reasons, if I could of got a little thicker piece it would of worked even better. 1st reason the heat from the light will bow the plexi glass if it is not taken care of with a fan blowing across the top. Second reason thinner pieces of plexi glass will shatter while working with them if you’re trying to make edges, and curves. The thicker pieces are very brittle still but better so be patient and take your time. Another draw back that you might need to overcome is on my tank I have a reinforcement on the top because it’s a bow tank connecting front with back. I don't know if you have this or not on yours so if my plexi glass sags it can only sag so much. Lots of people don't even use a top on their tank I personally feel as if I need something to hold down salt creep and fish, but my cousin has the coralife light with 4 mounting plastic clear legs and it works with or without a top just fine. Also you could go to a stained glass place and they will cut you custom piece or pieces of glass depending on how big your tank is, but be careful when cleaning it not to shatter it or something. I work in my tank a lot so I felt that glass was not ideal to be lifting and cleaning all the time without edges getting chipped I also don't know if glass could be cut to snug each pipe I've seen them do slightly curved stuff before but I think it would be one to many twist for a carbon tip cutter. Good Luck
