I used to have 2 cats and got an automatic feeder and fountain for them. I had to search just now for the fountain since it seems it's not sold in a lot of places.
https://rsc-store-media.s3.amazonaw...3525d08d6e5fb8d27136e95/p/w/pww00-13703_a.jpg
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Notice the humongous reservoir in the back. I think it held over a half gallon. To fill it, just lift it out of the base, walk to sink, unscrew valve, fill from tap.
Some fountains like the one above have filters for the water. You really need that since they're slobbering in bowl all of the time and that can't help the taste of the water.
Something else you can do to make the fountain attractive is to get a little seed cage that hangs off the side an into the bowl. Put some cat friendly seeds in there and in a few days you will have scrumptious cat grass. No additional work required.