when we were on tankwater, I just to just buy fluoride drops to put in out
water.(my chemist had to order it in) It wasn't very much at all, but I was
mainly worried about my daughters growing teeth, she was only 1 then. If
you're not sure what amount to put in, call a few school dental clinics, or
speak to your chemist, they have leaflets on this kind of thing. good luck

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