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  Topic Review (Newest First)
02-17-2013 09:36 PM
Re: Holding tank size

Consider replacing your entire existing setup with a composting head and never worry about holding tank size or capacity again. You'll also gain storage space where the old tank had been.
02-15-2013 08:21 AM
Re: Holding tank size

It will of course also depend on your head - i.e. an electric head with a macerator that uses either fresh or salt water as part of it's flush can take anywhere from 1.3 quarts to 1 gallon per flush (presumably for 'solid' flush only, but who knows).

Go big, but be mindful of the structural issues and weight. 400 extra pounds forward or aft can seriously affect the waterline and under body profile of the boat.
02-15-2013 07:25 AM
Re: Holding tank size

Originally Posted by ellenwhite2 View Post
We have a 15 gallon holding tank. With 2 adults aboard, we pump twice per week. I would go bigger......hmm. maybe that was poor choice of words....
No, you just need to train Bob to go in Slinkys litter box!!!


Ps. Coming your way soon...
02-14-2013 05:20 PM
Holding tank size

We have a 15 gallon holding tank. With 2 adults aboard, we pump twice per week. I would go bigger......hmm. maybe that was poor choice of words....
02-14-2013 04:24 PM
Re: Holding tank size

Our use is 1-3 gallons, per person, per day. I would plan on two gallons, per person, per day as a good average. And as you are cruising, just remember, there is not a pumpout at every stop. And when you find them, they often do not work. And when you find one that works, you better get ready for a nice charge. We got charged $25 for out last pumpout. So if you have to pump out twice a week, at $25/pop (which is very high, but I am making a point), how does that sit for your cruisin budget? Truth be known, most pumpouts are in the 5-10 range, but likely run higher in the keys.

I think for a couple, I would go for the 38 gallons holding tank.

We are fulltime cruisers.

02-14-2013 02:52 PM
Re: Holding tank size

You might want to take a look at RMBOA Blackwater Holding Tank Calculator
02-14-2013 12:11 PM
killarney_sailor Where do you plan to cruise? This can have a big impact on holding tank size.
02-14-2013 11:47 AM
Alex W
Re: Holding tank size

Don't forget that a very large holding tank (like 38 gallons) will also require considerable structure to hold it in place in rough seas (or in the worst possible case, a roll).

A 38 gallon tank will weigh ~400lbs when full.

Personally I'd rather have useful storage than another 18 gallons of crap...
02-14-2013 11:06 AM
Re: Holding tank size


Suitable tank size depends a bit on your cruising plans and your crew's preferences/habits.

I'd recommend you start your analysis from another direction: How often will you have access to pump-out and/or off-shore dump options?

FWIW: We've got a tank that's about the same size as your current one. We lived aboard for a couple of years. We did the Loop, though we did have a few extended stays in several locations (Brunswick, GA; Marathon; Oriental, NC; Holland, MI) -- and the only time the holding tank size became an issue was when we were on the Black Warrior stretch of the Loop above Mobile, AL.
02-14-2013 01:35 AM
Re: Holding tank size

Turkish regulations request 2 liters per day per person for two days. This might be a good start.
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