When camping in full hookups I always keep my grey tank closed until full. When dumping the grey tank it smells worst than the black? Would it be better to keep the tank open or closed?
As do most I leave both closed till time to dump. Black first then gray to rinse hose then shut. Aside from discussed we have been in two South Florida parks the last year and they have these very pesky sewer flies. Keeping the valves shut between dumps helps to keep them out. The gray tank in my experience can smell as bad as the black could be food stuff etc. from galley sink.