I suspect that your problem stems from hydrogen sulfide (H2S) in your groundwater. This is natural and common in many parts of Ontario. It is present in both the hot and cold, but more noticeable in the hot because the increased temperature makes it more volatile.
Bleach won't help it, nor will CLR. I believe you can use something similar to a water softener with a media to remove the hydrogen sulfide. You can also run the water through a trickling tower, much like a biofilter, to degas before it goes into your household system. Not very practical, however:-)