Backyard Aquaponics
A place to discuss aquaponics

So my FT is an old cast iron bathtub. At the moment I have a solid lifting overflow attached to it but it leaks a little bit. I want to re-plumb it so that it doesn't leak anymore and has a sturdy connection. There is a large hole right under the faucet where there used to be an overflow when it was used as a tub. I plumbed it by putting down pond liner then a piece of plywood on each side of the hole and cranking them together with bolts to create a seal. Then I took a hole saw and sawed through the center where I placed my outlet tube... right now the outlet tube is sealed by a couple of pond liner gaskets I made but it isn't that great of a seal. What would be an easy and fish-safe way of attaching this. What kind of glue that is available in the US is good for this kind of application? I was thinking I might just hot glue it all together and see how that works, as it may only be leaking from where the hose enters.

try uniseal for a tank or trough fitting and use a small smear of kitchen grade silicon sealer on all the contacting faces.