The Drinkwell pet fountain is very good for a person who is never really there to change their pet's water!
I would recomend it to most peaople with dogs or cats. I incourage you to buy a Drinkwell pet fountain for yourself and see how well it works!

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[updated on 2008-03-07 15:25:01 GMT]:
I will recomend this to people everywhere!

Pros: Wonderful

Cons: Best!

My daughter uses one of these for a cat with uinary problems. In the two years she's used it, the cat had only one infection. Dr. attributes this to drinking moving water from the fountain.

Pros: good for urinary tract

Cons: Can't think of one....

These are fun although if you have a cat that likes to play in water then it just becomes another mess to clean up.

Pros: Cats like it

Cons: sometimes messy

My cats love it. They will not drink out of a regular water dish not. They love the running water.

Pros: Running water, large extra water container

Cons: Hard to clean