I'm not sure I understand your question but if your pool at the bottom of your waterfall leaks it is probally because you didn't put some sort of sealer on the concrete after you finished. My parents have exactly the same setup in their BSMT and it doesn't leak because Dad put a sealent over everything that came in contact with water. Something you need to be careful with is water damage and mold buildup in areas that are not visible. You need to give the unit a couple of months to completely dry then put the sealent on it.
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Other people asked questions on various topics, and are still waiting for answer. Would be great if you can take a sec and answer them