ahoy wrote:

What excitement. I'm trying to install a new 6 gal waste tank next to
my head which was designed long ago as an intake-pumpout-to-the-sea
arrangement. The sanitary looking, white plastic tank has two 1.5"
in/out stubs and a 5/8" vent all sticking out the TOP.
So how do you evacuate the tank at sea? This all seems reliant on the
pump pressure of the hand pump which can't be much and would seem to
pump the waste but then leave the tank full of seawater. (48 pounds of
unpaid freight!). I'm not bright at things I've never seen. What am I
missing here? If the outlet were at the bottom of the tank it could
just run out as you opened a valve and vented, hmm? Thanks as always.

The outlet needs a pickup tube inside the tank that goes to the bottom.

Take the 1.5" thread-barb tank fitting to a hardware store...find a
piece of PVC that fits snugly inside the threaded end...it'll most
likely be 1.25" OD, but because wall thicknesses of both fittings and
pipe can vary, you want the fitting with you to make sure of a good fit.
You'll secure it with PVC cement.

The tube should just touch the bottom of the inside of the tank...then
be cut at about 25-30 degree angle. If it's flat across the bottom and
any closer than 3/4"-1", it's likely to become clogged.

Putting all fittings on the top of the tank is actually the best way to
do it...because a) it eliminates standing waste in any hose, which helps
prevent hoses from becoming permeated with odor...and b) hoses can be
disconnected from pumps/macerators/through-hulls to service 'em without
a spill. It also increases the useable capacity of the tank by 5-10%
depending on the size of the tank.

Btw...a 6 gal tank only holds a dozen flushes at most...for two people,
barely enough for an overnight stay in a marina or anchorage.

--
Peggie
----------
Peggie Hall
Specializing in marine sanitation since 1987
Author "Get Rid of Boat Odors - A Guide To Marine Sanitation Systems and
Other Sources of Aggravation and Odor"
http://www.seaworthy.com/store/custo...0&cat=6&page=1
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