Planning my wood bottom aquarium build. Trying to figure out the best way to do a standpipe/return to the sump. What type of fitting do I use to go thru the wood. I am gonna do a 2x4 frame with 3/4 plywood then silicone a sheet of bathtub surround for the bottom this will be my water proofing I need to pass the pipe thru 3/4 " of wood and the surround. Don't think a union is big enough any helps appreciated thank you