Sure, that would work to check for leaks. I didn't really wait much, I had batches waiting to be kegged so I put'em in there and worked through the inevitable issues. For one, the guy at the brew store sold me 1/4" beer line, way too big and foamed like crazy into the glass. People here set me straight, so I got 10 feet of 3/16 for each tap, worked like a charm. Stuff like that is hard to trouble shoot with water.