If you have a Big Lots near you they have the medium size (50 oz) Petmate Fresh Flow Fountain for $15. I saw it in a sale flyer today and went over to pick one up.
I have one for my cats already but it is 2 1/2 years old so I don't know how much longer it will last. It's a large and this new one is just a medium but I think it will be okay. This way I have a backup ready.
Just thought I would share. Here's a link to one just like it on Amazon.com
Fountain
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