The only way I can get mine to drink any water is to put a little drop of normal milk in it.

Don't get me wrong, I am def. not advertising this as being good for everybody's cats but mine have had this everyday for months and so far, touch wood tummy's seem to be ok.

Always makes me laugh actually because if there's the merest trace of milk in the (warm) water they wolf it down. Plain water - forget it, they won't go near it and never have done. Strange creatures.......