yeah that's not the aquarium safe stuff...
https://www.aquariadise.com/aquarium-safe-silicone/
The one they left off this list, that I've read everywhere is the go-to for custom tank builders, is the momentive RTV100 series - RTV108 for clear, RTV103 for black
https://www.aquariadise.com/aquarium-safe-silicone/
The one they left off this list, that I've read everywhere is the go-to for custom tank builders, is the momentive RTV100 series - RTV108 for clear, RTV103 for black