Also. We have bottles for winter (leave them up year round) and LOVE these easy to manage little bowls as an additional water source when it isn’t sub- zero. Any 1L water / soda bottle on the outside of the hutch will keep it gravity filled. Larger bottles don’t tend to work as well in my experience.
You do have to clip a small spot on the cage for the small spot to come through. Wrap the tabs around the cage wire and make sure it is as level as possible.
Make a wire (or whatever you have on hand) loop to secure the bottle to the outside of the cage. Fill the bottle, drop it into the small side of the bowl.
To clean, pull the bottle out, flip up the bowl to dump any remaining water, wipe out as needed.
Up sides- my bunnies like the bowl a lot better than the bottles, and drink much more consistently from them. They also will dip their feet in them when it is hot out and that seems to be their preference over the frozen water bottles that we offer on those rare occasions in our climate.
Down sides- if the bowl isn’t very level, or your bottle is too large, they can tend to “leak” over the side of the bowl. Which. Attracts more yellowjackets than the open water does on its own. We live in the PNW and yellowjackets are an issue. If you live somewhere with more summer wind, I doubt that you would have the same problem. But. I’ve only had bunnies living here, so.... I can’t say for sure
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