My artistic skills are lacking today but I gave a rough idea of what I am planning with just as equally rough drawing. But the idea is to have 3 layers of slate, one for the shelf so the water can run down. Another to set up the base of the cave and prevent a curiouse snake from getting stuck under there by the outflow of water and then the cave on top for hiding, the entrance will be side facing and not over the bowl. The two pipes I have drawn (aka the crapy lines I drew) will both be going out of the tank into a bucket for ease of cleaning water out and probably will have a natural filter set up, that is where the pump will live. One tube to drain the bowl and another to go up to the pvc pipe that will put the water out. This is a design we have used with both poison dart frogs and our aquariums in the past and it works really well. To prevent substrate from getting in the bowl i was going to do a ring of slate around her bowl to help keep it clean, its what i do with my tortoises and it worked out great for mostly keeping the water substrate free.
Also just a reminder this is still going to be for in a years time, she is not big enough yet for a 55gal aquarium so the design might change over time.
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