As I threatened, I ripped out my Attwood shower sump because it was so unreliable. Replaced it with a Whale Gulper diaphragm pump since I already had switches in both heads to turn it on and off. Works great, but with one unexpected side effect. It can pump faster than the shower sprays water, so I get this loud pumping sound coming up out of the drain. If I run the shower awhile before turning on the pump, this goes away, but I'll sure never let it continue to run by accident. Can't wait for the first guest to use this.