John,

You peeked my interest so I researched further and indeed they do exist. The following American Ground Water site has an interesting article on it see link below.

The problem is I would need 90 gals of chlorine to kill the little critters 1:100 if one reads the article. So I think I will just have to live with them.

Thank you for helping me think.

http://www.agwt.org/bacteria_info.htm