I am creating an overflow pipe for a rain barrel. Will be creating my own 3D-printed "flange" connector. Half of it will be submerged. Its "flaps" need to be glued to the interior wall of the rain barrel. What kind of adhesive would I use for this? It needs to be impermeable to water (water-resistant) and not degrade over time in the water. As an adhesive, it needs to be strong enough to withstand some accidental bumps of the overflow hose which will be connected to the connector.