Wow! What you must be imagining! At this point I'm putting in two quarts of icewater a day into about a gallon in the tank so the water probably isn't in there more than a day anyway. And the water is run first thru a four stage reverse osmosis system. If you're giving your girls tap water then they're getting the same chlorine, floride, VOCs and possible toxic minerals from your city system that you are. If you're filling you hanging waterers from a hose that's not designed for drinking water then you're probably putting in chemicals from that (see warning tags on hoses) and if you're using plastic waterers who knows what comes from those into the water -- ever drink water from a plastic bottle that has been in the heat for a while? You can taste the plastic. Which is why I'm using a glass tank. Re: your concern about a "fish tank piped to my yard" -- it was never used for fish LOL! Just a way to find a glass container that would work.