When the tank still has structural integrity, sound walls, intact baffles, a functional lid, repair is often the right call. A broken baffle, a cracked distribution box, a damaged pipe connection: those are repairable components. When the tank itself has deteriorated to the point of groundwater infiltration, fractured lids, or compromised walls, there's nothing to patch that holds. David's tank had no repair path. The structure was gone. Replacement was the only option.