This is the fist time I've had a sump (overflow tank). How can I get my drain pipe to stop making the flushing toilet sound? This can't be normal. Am I going to have to install a shut off valve? It goes away after a while and with much fiddling with the tube (which I think is too long). But if I ever shut off the pump for maintenance, it takes forever to get the excessive gurgling to go away. Do I add a shut off valve so the drain pipe doesn't drain into the sump, shorten the hose, or just be patient?