well, it still could have been something different but a lot of times tap water doesn't have a pH of 7. so you have to check with your local water service to find out if there are excess amounts of florine, or hard metals. i know places where the tap water is 5.5 all the way up to 8. so the prolonged exposure just weeded out the weaker tads.

sometimes tads just dont make it, either they weren't strong enough or something happened when they were still developing that screwed them up. there's really no way to tell.
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A room of herps.
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