THIS THING!
The Drinkwell Pet Fountain Cleaning Kit

I have been cleaning my Drinkwell Platinum fountains with a toothbrush and sponge for years. It was a messy job, it never felt complete, and it took more than ten minutes. I came across this one day while I was trying to pad my Chewy.com order up to $49 for free shipping, and I am so glad I did. There is no residue left over in the fountain, it’s clean in five minutes, and you would be surprised at all the muck hiding out in the fountain nooks that the brushes coax out effectively. The channel from the motor to the waterfall (can’t even get your pinky finger in there) is stuffed with grossness until you brush it out.

But it’s also not just about the fountain, if you have a Drinkwell or something similar, but that these are great brushes to use on your small animal water bottles. I have been wondering for the longest time why the guinea pigs favor one bottle over the other. I check the tip to make sure the ball moves and it’s wet, so it must be fine and the piggies are weird?
I was wrong. I cleaned out the nozzle on their favorite bottle and thought to myself “oh yuck. Why are you always drinking with food in your mouth?!”. A bunch of muck came out. After I gave it back to them, I pulled the bottle they rarely ever drink out of. As soon as I stuck the brush in the nozzle (this is the small brush meant for the pet fountain motor), there was resistance from the ball midway up the tip. I ran hot water through it and forced the brush to move the ball further up the sipper tube, and this wad of old guinea pig cud flushed out into the kitchen sink. I spent more time cleaning it out until I thought it was ready, and I gave it back to the girls with clean cold water. Murphy started drinking out of it immediately.

It doesn’t matter how much hot water or vinegar you use, there is always muck hiding in these things until you get yourself a set of brushes.