[Chuck]

how are drain lines typically connected to a grey tank? the fittings must need to be non-permanent, so tanks can be removed/repaired/replaced. I don't know the official names for most of these plumbing joints, but I'm wondering about a "slip fitting"(?), or do they use those rubber splice thingies w/ the hose clamps on either end?

what about splicing the black pipes that were used way back when (polybutylene?) to pvc? is there a special glue, or do they have to be spliced another way?

how about dump valves..they make them 1 1/2 inches...how does that connect to a pipe? glue on either pipe, and then 2 halves that form the housing screwed together?

I'm thinking (again....or still) about a grey tank retrofit. From the schematics and exploded diagrams I've obtained, it looks like I can just connect existing drain line to the proposed holding tank outlet at one end, and add a valve just upstream from where it currently dumps into the "collector" (what A/S calls the 3" pipe between the black tank dump valve, and the sewer outlet).