Capacity of holding tanks and water tanks

[Sailsarefull]

I am looking a boats to begin cruising. The boat is a 36 foot with 6 gallon holding tank and 80 gallons of water. For those cruising, are those sufficient? The holding tank seems small. The water I would like to be 100+. Could put 5-10 gallons in portable tanks on the deck. But, holding tank more of an issue.
Always appreciate the input from those way more experienced than me.
Thanks.
John

[SailFastTri]

On that size boat, 80 gallons is about all you'll get in a production boat unless it's unusual.

The 6 gallons holding tank is a joke. You will want at least 18 gallons for black water. More is better. People's needs vary quite a bit but the average person flushes about 3+ gallons per day even if they're trying to minimize flush water.

[Sailsarefull]

Thanks. In all my research, those that are not just daysailing desire 15+ for holding tanks.

[dlymn]

You only need a black water holding tank when you're in a port. It depends how accessible shore toilets are. With a hand pump toilet, 6 gallons might store10 usages. If you only use the tank when you're tied up and only in an emergency, then your tank might do.
80 gallons of fresh water is fine if you plan to be away from ports for even over a week. If you're at sea for days on end, you can arrange things to use very little water. At sea you don't need to wash clothes, shower daily, cook with large volumes of water or even use fresh water for washing dishes You need 4 pints per person per day for drinking. If you're going to visit ports every few days then 80 gallons is fine.
Make sure that you have excellent filtration and chlorinate your water.
Why not run with what you have and maybe change your living habits a little.

[Sailsarefull]

Thanks, I appreciate the feedback. Am ok with the water tank. Might try to increase the holding/black water tank if it isn't too much hassle.

[Tellie]

Depends a bit on your definition of cruising. Every cruisers definition is different from the next. On a 36' boat my personal choice would be to lose the holding tank and associated system altogether and go with a composting head. Far less hassle and a lot more capacity. Once I went with a composting head I never looked back and wondered why I spent so much time with a traditional head system in the first place. It gained me more storage room on the boat by getting rid of the holding tank and the plumbing needed for an old school head system. The smells were gone and maintenance was a breeze, no more joker valves in 10 foot seas. Again, depending on your definition of cruising 80 gallons of fresh water holding may be sufficient or it may not. I'd be more inclined to look at a small watermaker. Consider the cost of up grading the head holding capacity and or fresh water tankage and add that cost to a small water maker instead and your 80 gallons fresh water capacity is no longer a concern. Also it would free you up so, and don't underestimate this value, you don't have to schedule weekly stops or ports to find water. If you are coastal cruising what you already have is fine. But once you go off shore to more remote places things change as does your personal idea of what your comfort level is.

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[Mike OReilly]

I guess it depends on where and how you cruise, but 6 gallons for a holding tank seems completely useless to me. You'd get a 1/2-dozen uses before it's full. Unless you're always tied to a dock, or always able to get out past the three-mile limit, 6 gallons is a joke. I used to cruise with a 32 gallon and then a 25 gallon holding tank and felt that was inadequate.

Tellie beat me to it on the composting head suggestion. For cruising couples on smallish boats, it's the best possible solution. Simple, effective, safe, and it frees you from the tyranny of pump outs.

An 80 gallon water tank isn't bad, again depending on your cruising plans. Bigger is better. I'd definitely consider a watermaker if my tank was that size. We carry 200 gallons and manage quite fine (two people, anchored out most of the time), but even here I am seriously thinking about going with a watermaker.

[Kenomac]

Our holding tank is 15 gallons, but.... We've never used it. The through hull is open all the time because we refuse to allow our boat to succum to encopresis.

The ocean is a natural composter, no need for specialized equipment. You're just fine with six gallon capacity... flush away.

P.S. Only American boaters worry about this $hit. There are no $hit police outside America. Just as soon as my good friend Mike clears out of US waters, he's going to wonder why he ever switched over to a composter. He's going to switch back and flush overboard in a jiffy.

[Mike OReilly]

Originally Posted by Kenomac

Our holding tank is 15 gallons, but.... We've never used it. The through hull is open all the time because we refuse to allow our boat to succum to encopresis.

The ocean is a natural composter, no need for specialized equipment. You're just fine with six gallon capacity... flush away.

P.S. Only American boaters worry about this $hit. There are no $hit police outside America.

It's not about the police Ken, it's about not crapping up the environment. Our anchorages are mostly smaller, contained areas. A few people flushing their excrement over the side all the time would quickly turn these areas to shyte.

If you're able to be underway, then no problem. "The solution to pollution is dilution," so dumping away from shore is great. But for much coastal cruising around here that's not very easy. On the Great Lakes, it's impossible.

[SaltyMetals]

to Kenomac; I must make sure that i never anchor downwind of an Oyster 53 and go for an evening or early morning swim in case it is you. It is not difficult to respect other people's desire to swim in clean water, it is not difficult to switch over to the holding tank. If you have one then I am sure others would wish that you use it.

[rbrentp]

A comment on composting. M current boat came with a composter. I called the factory and they described it a s perfect for a couple for a weekend with two weeks time between visits to the cabin. I am sure there are others that compost more quickly or have greater volume or something. It was four times the size of the typical low volume head. Not saying they don't work...I love the idea...but that and access to good coconut shavings or whatever the current medium is makes the composter a definite trade off on how you cruise. On our low volume head and a 13 gallon tank we get about ten 2s and twenty 1s. (gender has an impact). Two people for a three day weekend it works fine with spare capacity. So back to what is cruising and where?

[hamburking]

The small holding tank is to make the boat legal. many ports and lakes require a holding tank be present, or you are subject to a fine. I expect your boat has a Y valve, so that head waste can be expelled overboard. These are illegal someplaces. However, on the ocean, especially out of sight of land, head waste can go over the side.

Some places, like Antigua, don't require holding tanks. Some of the anchorages are disgusting, with floating excrement everywhere. Fortunately, tides and currents take most of it away daily.

Personally, I pee over the side. At my home dock there are shore heads. I find there is no need to use the head aboard. The ladies disagree. I have gone entire seasons without using the head. My marina doesn't have pump out facilities, so getting a pump out is a bother and a cost.

Also, the fee for pumpout is per boat, with no adjustment for volume. It costs the same to pumpout a mega yacht with a thousand litres of crap as it does to pump out my small head waste tank, with maybe 10 gallons in it.

[Captain-Avenger]

Originally Posted by Kenomac

Our holding tank is 15 gallons, but.... We've never used it. The through hull is open all the time because we refuse to allow our boat to succum to encopresis.

The ocean is a natural composter, no need for specialized equipment. You're just fine with six gallon capacity... flush away.

P.S. Only American boaters worry about this $hit. There are no $hit police outside America. Just as soon as my good friend Mike clears out of US waters, he's going to wonder why he ever switched over to a composter. He's going to switch back and flush overboard in a jiffy.

I can't believe that somebody would admit in writing that they leave their crap all over the place for other people to worry about. I like to think that where I go the water is clean enough to just jump overboard and enjoy an afternoon swim without the worry of coming back on board with somebodies feces stuck in my hair. In the US I like to think that others are more respectful of the rights of others to a clean and safe boating environment for all.

[CLady]

60 gallons of water capacity seems to suffice on my 40 footer--it was enough for three of us for 24 days, of course, we used sea water to wash dishes, and no showers with fresh water. We had 10 gallons of water in containers, so the boat had a total of 70 gallons of water.

[MarkSF]

"you only need a black water holding tank when you're in a port."

Or within 3 miles of the US coast, or in a no-discharge zone.