It is the lowest point, in this case the outlet, of my newly designed gravity drain system. No pumps, Y valves, macerators, etc. My head
will discharge into the top of the tank, which I have mounted approx. 2’ above the waterline. We are a sailing catamaran
so angle of heel is of little to no concern in my case, I have all of my fittings-vents, pump-out, 4” clean out access port, and inlet from head
on the top and of the usual 1.5” variety, except the aforementioned 4” access. However to reduce the chances of clogging, the gravity drain fitting is a two inch exterior slip fitting(nipple)which I had attached via spin welding so that 2” ID hose can be double clamped to it and then attached directly to my below waterline thru-hull for discharge. This will minimize my hose connections below the tanks
I have found a supplier of butyl hose from the Uk in 50mm, which will work
in my application if need be. Just curious if anyone knows of any other options.