Edit: I found an infinite water hack by holding a tube of Churu, a treat that's like crack for him above the water so he was forced to get water with each lick. I would stop squeezing the tube and he would continue to lick for a few seconds, not realizing he wasn't getting any Churu. After walking away I saw him taking a few licks out of the bowl. So fingers crossed he starts using it himself now.
He's had a plastic water fountain for more than a year that he instantly started drinking from. It's starting to get a bit grimy and the pump is failing so I bought him a new stainless steel one and swapped the old one with it.
He stopped drinking water for a day before I put the old one back. They're both running and now he only uses the old one. Is it safe to just take the old one away again so he'll be forced to use it when he gets thirsty enough? I'm guessing he won't just refuse to drink until he dies?? I'm worried about health problems if he doesn't drink for a day or two. He's 2 years old and otherwise healthy.
I know he's fine with the new water taste because he'll drink it out of a spoon (and he sees where it comes from), and I even put some on the flat side part of the stainless steel fountain and he licked that up. He just won't drink out of the flowing bowl. I also turned the water flow off and put catnip in the water, and he tried to knock it out with his paw but wouldn't directly drink from it.