I have designed a pool for small animals and crustaceans. I have hermit crabs and I did not want to change out their water bowl everyday. Plus the store purchased bowls where very small. So I made a pool they can really walk thru and bathe if they wanted. The design was to have the pool at the corner of a tank.

The designs utilizes a water bottle, like the one in the photo, not soda bottles. Take a look at the threads to make sure you use something similar. The bottle screws into the pool and is held securely. Need more water, use a larger water bottle.

My hermit crabs like to climb the bottle and was able to tilt the pool enough to have the pool pour over the side emptying the bottle. Pool should be placed on a flat level surface and staked down if you have an animal the may tip it over.

Nothing special to print. I printed mine at 15% infill. 

Enjoy!