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I have a bathtub with a plastic (I think) surface layer which has a small crack in it. The crack is at the bottom, on the inside. Some sort of rusty liquid has now started to ooze out from the crack, which feels less than hygienic.
Before I replace the whole bathtub, I'd like to try to repair the crack. What approach would be the best here? What sealant would be recommended? It obviously needs to be both water-resistant and non-toxic.
I'm thankful for any advice!