I got a Cat It fountain from Amazon last fall. Green bucket kind of bowl with a white daisy stuck on top the water drips off of. Had some doubts but it wasn’t expensive.
They fracking love the darn thing. After the initial bug eyed OMG gasp when I turned it on, they took right to it. At first you can fill it all the way up to where it’s over the top of the filter so they can lick from the pool instead of as it drops. But mine learned to lap it right from the falling stream in a couple of days. It holds enough water to be pretty heavy and refilling is easy, dump it in, don’t need to take the top off. Holds about 1,5 or 2 liters so good sized.
One thing I liked over some of the others is the rim of the bucket and the fountain are about 8-10" off the ground so right at chin height for most cats, no spill, no mess. Have to do something else for a tiny kitten, which you know will drive them nuts trying to get at that moving water for a month or two.
It comes with 6 or so filters but, according to the reviews, coffee filters work just fine. Last about 8 weeks, then they stop the flow out the top of the daisy. NBD, just change before it plugs the flow. Little aquarium motor, cord could be a little longer but pretty easy to deal with. Quiet too, unless you let the water get lower and splash inside the bucket like a fountain and even that is not unpleasant.
Mine were drinking out of the toilets and totally ignoring a bowl unless they spilled it, now they cannot resist a swallow every time they pass. And I can keep track of how much they are drinking, usually between 1/2 to 3/4 of a cup daily between the three of them, they aren’t big cats either…well, 2 of them aren’t.
Anyway, we all like it.