I have a 70G Rubbermaid Tank that will eventually be just a sump for my 120g but for now it is loaded with live rock and corals. I don't have a strainer on the inside and sure enough it got clogged. I was able to free the clog and want to put a strainer on it but I couldn't get anything to fit. I can't see it and can just barely wiggle my arm down to and feel the opening. I thought I felt threads and figured since the outside end was threaded 1.25" that the inside would be as well but I can't screw a 1.25" strainer onto it. Does anyone have one of these and know what is needed to get a strainer on it?