Speedy only drank 2 times. Once was just after she'd thrown up by eating too much. Both times were because she was really dehydrated and then, once, I had to drip water on her nose the first time she only drank when I moved the water she was soaking in. She won't drink water anyway, even if I drip water on her nose.
Zoom is starting to drink, once in a while, when I drip water on her nose while soaking.
Miss Y was the only other dragon we had that drank water.