If you can find the 3M 4200, it will normally dry before you can get done running your bead. Nah, just kidding, but it dries fast. Sikaflex maybe a few hours, PL maybe overnight. Depends if you are using it to fill gaps, or using it under a sealing ring, i.e. bottom drain. Filling gaps of course takes longer, putting it on a sealing ring you can add water almost instantly.
Just for reference, there is also a caulk that can be used under water called "Boat Life" Life Caulk, it is a polysulfide rubber and dries almost the instant water hits it, and sticks extremely well to wet or underwater surfaces as long as they are clean. Is is fish safe???? I never checked into it, but I'd use it.
