The sump has been holding water for 2-3 days now no issues. One of my cats even jumped in it by accident and splashed around clawed the side to get out. No issues. the paint held up. It seems to have soaked into the wood so it has a bit of wood grain texture to it but is very waterproof. Water still beads off it easily.
In other news I am cleaning up a 55 gallon for a planted show piece in the house and I got myself a new pleco to go in the 55. He is currently hanging out with one of my Krib pairs. He is a beautiful L007. Commonly called Galaxies. But this one was labeled as a "Vampire Pleco" which is the other name for them. My LFS was unloading their new fish so I got first peak and took him before he even hit the water. He is very dark, nearly black, with the white spots. The L007s commonly are a dark brown. But this one is near black. Looks great.