[Chris Burkard]

It may be possible to do that, but you have to take into account the distance from the source to the sumps and height above the sump the source is. If the source is lower than the grey water tank, then you will have to drain to a smaller sump box and then pump the water to the grey water tank. I believe the shower is lower than the grey water tank, so you have to have a sump below the shower. The other issue is distance. A head sink located in the bow is not going to drain very well to a grey water tank located in the engine room 30 feet away. Grey water tanks are not needed in many cases, but they do reduce the number of thru-hull fittings up and down the sides of the boat. Every fitting is a possible leak. If I had my way, everything would drain into a single manifold and then drain to single tank or thru-hull for a clean set up with only one or two thru-hulls, but many layouts don't allow this type of set up.