I have had a tankless water heater for ten years now. Love it. But I have to clean out my shower heads and faucets every month or so. The clothes washer is the worse- it looks like coarse beach sand and clogs the screen on the hot water supply line fairly quickly. Overall a pain in the rear. The tankless water heater creates a sort of sand that is a calcium lime product and sends it out the hot water supply lines. I have installed a whole house filter. I have installed a whole house water softener. I have a "lime fighter" installed on the supply line of cold water going in. Nothing stops it. No plumber is willing to install a coarse filter on the outgoing to catch it all; they say it will leak because of the temperature variation. I am willing to live with a tupperware container under the filter that I will soon install myself. Any one solved the same problem?