Bearded dragons like dry conditions, so personally i will never put a water fall in it. Also ideally bearded dragons get their water needs from misting and the water present in the salad they eat.
According to Dachiu Dragons care sheet (
Frequently Asked Questions - Dachiu)
"Bearded dragons require a dry cage, but need to get a lot of water from sprayings and eating fresh vegetables. The hatchlings should be sprayed twice daily on their heads, keeping the spray directed onto their heads as long as they keep lapping up the water. Adults should be sprayed a few times a week. This simulates the natural way dragons get water by licking up drops of dew they find on plants in the morning. Some do learn to drink from a shallow water pan, but if they get thin or dehydrated it will be necessary to get them to ingest more water by increased spraying and by misting their fresh vegetables. If using a water dish, the water MUST be changed daily and if the dish has been defecated in - it must be cleaned immediately.
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