If you really want to do it, I would recommend putting a silver kill coil in the inlet to the "loop" and even a filter would be great.
If the water is cool enough to condensate you do have to remember that the water blocks can and will condensate too.
Originally Posted by bl1nk
Yes, I have seen a build where someone ran directly from their tap.
However, it's not a good idea; tap water is full of minerals that will mess with your loop.
he isn't using city water so I don't know how you could make a statement like this,... or likely you didn't read his whole post?
I know that a lot of lake or well water systems don't add anything to the water, but of course there will be lots of extra junk in the water that isn't a good thing to run in a loop (which technically this isn't a "loop").