I had a leak in the plumbing coming from the black tank. Going to remove the plumbing and redo with better bracing. I have a question about the fitting going to the black tank. I see a screw clamp around the fitting connected to the tank and what looks to be plumbers putty. Does anyone know if I should be able to remove the clamp and pull the fitting from the tank? For installation is that plumbers putty or something else? Thanks for any insight and suggestions.