What have you tried so far? And most importantly, are you sure the nipples are working properly? If you haven't already, I say just take away the dishes. They're pretty smart crittersNow, if you've done that already and have noticed significant die offs, here's what I'd do. Hold a mouse/rat up to the nipple, tap it with your finger and get the water flowing. Once one or two know how to use it, the others catch on pretty fast. It may be time consuming, but try with at least one or two in each colony. Good luck!