Sealing butyl pond liner

I'm building a waterfall coming down to our existing butyl-lined pond (I hate duckweed), and I'm using offcuts of butyl from the original pond construction to make the waterfall/pools. The question is this: has anyone successfully used aquarium-grade silicone sealant to bond/join butyl liner? The proprietary leak sealers from aquatic shops is PROHIBITIVELY expensive, and I thought this might be a cheaper (and also more manageable) alternative.
Any thoughts would be welcome!

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Re: Sealing butyl pond liner

Reply from Nicole Martin

I have just tried Pondpro2000, it is EPDM as well but in 100% liquid EPDM allowing it during the "curing" or drying process to find its way into the small superficial cracks and crevices to seal off pond liner leaks. Here you can get more details: https://www.pondpro2000.com/epdm-pond-liner.php