>I found the article on the Parallex website: > > >I still think it's a neat solution, cheap too. I was envisaging a tube that went down into the water. have to think how I can apply this to a water butt. >If you put a PIC on top, you might as well send back >the exact water level! True, but also measure the temperature and turn on some mild warmth if it looks like freezing, so the water butt doesn't get damaged, in my case. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist