Constructed my Hydro cup using a 16oz clear cup and punched a hole about 4 inches from the top. I bought a plastic 1/4" O.D./ 3/8" O.D. and screwed into hole. Then I cut the bottom off of a small tupperware container and taped it to the top of the 16oz cup with duct tape. I cut a hole in the bottom fastened to the top of the cup just big enough to hold the net poy from falling in. This was then all flex sealed and dried. A hole was punched for the air line and stone. A resivour was constructed also but is still being patched with flex seal. Should be fully functional, closed loop in the next week or so. This should be fun! Much love to all!