I do handywork/maintainence on some rural property in N.CA. and was working on a plumbing leak in the guest cottage. I decided to drain off the water heater since it probably hadn't been done in quite a while. What came out, in fits and starts, was gallon after gallon of this weird whitish slime. It looked like that Shout stain remover (actually, it looked like something else, but isn't this a family oriented forum?) and it didn't smell at all. It's a compact electric about thirty gallons, and it's supplied by well water that's a little hard. The client doesn't use the appliance continuously and shuts it off at the panel when there are no guests. I would say that it's on about 15 of every thirty days.
Has anyone seen this? Can it pose a health problem?