dyi for 100 gallon reef tanks for adding water mass and cutting pumps needed works grate on plex tanks that are drilled 55 gallon drum made of plastic 1 swimming pool or spa pump 110 most be able to do 3500 gph or better and 15 feet 1" soft hose and PVC fittings from outlet of tank to first bung hole on 55 gallon drum connect wouse fitting for size of outlet hose that u have next from the next bung hole to pump intake wouse size accordingly to hook them up from from there u can make gang valves to split it up to go to where u need it i run my to 2 return ports on my tank with octopus wave makers on them one line to my 40 gallon fuge and my protein skimmer with a small return line and pump going back to my tank with this i have cut down 6 power heads and have much better water flow in my tank with this my fish and every thing has been much happyer :D