I'm using two Hydor Koralia Nano 240 aquarium circulation pumps in a 5-gallon tote. They've been through three 72-hour cooks, and several shorter ones without issue. They've been above 180F for extended periods, and while the black plastic did take on a more matted finish, I didn't see any deformation. They say they're 240GPH, but they provide a very wide flow pattern for gentle circulation - I think they're designed for coral beds. They can be found at http://www.amazon.com/gp/product/B0036S4YZ0/
