So in putting together my first sump I had a hell of a time hooking the hard plumping to the pump. both pumps I used had a 1/2 inch threaded "spout" that I tried attaching 1/2 to 3/4 inch couple or 1/2 inch barb. I used pumpers tape with five wraps. Every time it leaked when the pump was running. How do I avoid this?