I have this at the bottom of my 60 Qt Ice Cube cooler. It is PEX tubing and a large grain bag zip ties over the nipple. I get no grain at all, and it would be pretty much impossible to stop up. I put a plastic cutting board on top of it so the mash paddle doesn't grab anything. I also drilled holes in the lid bottom for sparging and run the sparge water into the top. When I had a round cooler for 5 gallon batches, I had a 6' coil of hard vinyl tubing with holes drilled in it.
