What Size Holding Tank? (Merged)

[Cheechako]

Yea, that's a good point. I always figured you wanted some liquid in there or it could cause problems..... and there's allways the taffrail.... :>)

[lorenzo b]

I've got a 325 gallon tank down in the engine room that I plan on dumping some time next year if I really need to. It doesn't seem to be filling up very fast.

[GypsyHawk]

I appreciate this range of great response and thank you all. As usual the advice varies, as does that of the "experts" in print. Do you all feel the same anxiety before committing to a significant course of action? What I have gleaned so far that makes good sense - a 20-30 gallon tank (although us Aussies think in litres), solid construction and well secured (not a bladder), if possible above waterline with direct fall to through-hull fitting from beneath tank so no pump/macerator required (although I have been cautioned about having an outlet at the bottom of a tank), pump out option through deck fitting above, a gauge to measure how full the tank is. All of this within parameters of available space and cost. And I will look up the Peggie Hall reference. How does this sound?

[Bash]

Our two holding tanks total 190 liters. We can lie at anchor two weeks without worries if it's just the two of us, or one week if we've got non-boaters aboard. Amazing how much less water I require for a flush than the inlaws.

For our non-metric friends, that's two 25-gallon tanks.

[dskira]

The probleme with the gravity dumping is the solid and paper can clog easely the system. A manual pump help by pressure to reduce the solid.
It is my own experinece. the gravity dumping works with a valve with a large diameter, 4" will be the minimum. But the cost is quite prohibitive.
On a small boat I will go for 20 gallons. More start to be a probleme on space.

[lorenzo b]

Hi, all you eco friendly nature loving sailors out there. Care to say hello to the elephant in the room?
So I'm on Yachtworld looking at a beautiful Beneteau sailboat some 55' long with three staterooms and three bathrooms and a frigging 25 gallon holding tank. All sailboats are built like that. If you have room for three bathrooms, how about a 250 gallon holding tank so you don't dump your sewage where we are all swimming. If you are going to anchor in that lovely bay for a week, how about a tank that will serve 4 adults and three children for the time you will be there?
Do you really expect others to be polite when you anchor next to them for a week and dump your crap in the water?

[Last_Mutineer]

Originally Posted by lorenzo b

...sailboat some 55' long with three staterooms and three bathrooms and a frigging 25 gallon holding tank. All sailboats are built like that.

They are?

[rgscpat]

Was the boat maybe built for the Caribbean charter market or for sale in a country where overboard discharge standards and sensibilities aren't as careful as they are in the USA? Some of those boats seem to be pushing so hard for interior volume for cabins and spaciousness (a gigantic salon looks so nice at the boat show) there isn't much room left for stowage and tankage. Especially if the boat is expected to spend lots of time in marinas or short-term charters with the users going ashore almost every day, the builders may have decided to get away with a small tank.

[ShaunJ]

My 432 Beneteau has a 60 gal holding tank, I think it is too small for a family of 4 for a long weekend.

[DeepFrz]

You know those "through hull bungs" we always hear about? Maybe they serve a dual purpose.

[boasun]

I'm still waiting for them to require diapers on every fish in the seas

[DeepFrz]

This thread got me curious so I started looking and the first 2 quality yachts that I checked, Waterline and Oyster do not say how big their holding tanks are. Does that mean that like the rest of the herd they are woefully inadequate? On the HR-54 specifications they state 2 x 21 us gallons.

[Bloodhound]

Hmmm... Overtankage, over eating and over weight? Seriously, there are ways to make a smallish tank work, like following the yellow/mellow and brown/down ditty. Sixty gallons is a helluvalotta crap me thinks!!! You have to stop acting like you're connected to the city sewer system.

[Randyonr3]

the holding tank is probably just for the "Black" water or the toilets.. and most people on a boat keep the old " If its yellow, let it mellow and if its Brown, flush it down".. to keep the smell down we keep a squirt bottle of "smell good stuff" on the counter.. after the use of the toilet, squirt a little in the boul and all is fine..
Back to the topic, we have a 7 gallon holding tank in our 42..and it will last the wife and I about a week before we pump it or dump it..

[nv5l]

Lorenzo, could you provide your specs for comparison?