Peggie,
Yes, your description is better than mine, it is a sump. The sump(tank) will
be about 10 to 15 gallons with a float switch for the pump.
Steve

"Peggie Hall" wrote in message
.. .
Have you considered installing sumps instead of a tank? Gray water tanks,
because they contain food particles, cooking grease, soap scum body oils
and a whole bunch of other thing are MUCH harder to maintain and keep
odor-free than black water tanks. Sumps, otoh, can easily be flushed and
cleaned...they'd solve your problem and be so much easier to maintain than
a tank.

Otoh, maybe what you're thinking IS a sump...how large a gray water tank
are you envisioning?

Peggie

Steve Lusardi wrote:
Peggie,
Thank you for your reply. No, I have no intention of combining black and
grey water. The application is a sailboat. Sailboats live on their ear.
All drains are effectively below the waterline. In that light, draining
through conventional water traps into a large grey water tank with one
through hull and a single pump and check valve allow facility useage
under all points of sail in all weather conditions. To me, this is highly
desireable and is a better solution than shutting all outboard drains in
heavy weather. This solution is not available to all designs. There must
be adequate headroom and bilge depth to facilitate it.
Steve


"Peggie Hall" wrote in message
.. .
Steve Lusardi wrote:
Does anyone know what the mimimum slope of this drain can be that will
not cause clogging? I really do not want to use a second grey water
tank in the forward end which will cause loss of space and another
through hull fitting. It is preferable to use one large tank for the
whole boat.
Why are you installing a gray water tank? Gray water (galley, bath and
shower water) can go directly overboard in all coastal waters and,
except for only 2 or 3 places, on all inland waterways too.

If you're mistakenly referring to toilet waste (black water) as gray
water, holding tanks should be within about 6' of the toilet--'cuz
that's as far as bowl contents will move in the amount of time anyone
will spend flushing. So if you want to avoid leaving waste sitting the
line, a single large tank to serve two toilets at opposite ends of a
larger boat isn't a good solution.

If you're thinking of combining black water and gray water in the same
tank, CG regulations won't allow it. Gray water and black water plumbing
and tanks must be completely separate...can't even share a common vent.


--
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://shop.sailboatowners.com/books...ku=90&cat=1304




--
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://shop.sailboatowners.com/books...ku=90&cat=1304