Theo, the water runs into and out of the tank within the tent structure, so no hard water evident. I'm still just a little nervous about the really cold weather to come. I guess if I lose 'em, I lose 'em. I still haven't used any heater, so I've got the option of turning that on at some point. I don't consider it a fire hazard, but just the same I'd rater not run a heating element until absolutely necessary.
