Some of the best stuff that I have found for sealing leaks is made my a company called ProForm. It is called Dum Dum. I am not even joking, it is the best stuff ever. It comes in strips and is similar to plasticine. You just press it into place and form it with your fingers. It stays flexible and sticky and even works when the surfaces are already wet. You can also paint right over it, no need to wait for it to dry, because it doesn't! It is technically a form of butyl rubber caulking, but I like the name Dum Dum better. Heres a
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