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Composting toilet

Sep 18, 2014
22
Wharram Tiki Belfast ME
Been reading about composting toilets for use on a boat. Anyone have any experience with one?
Yep, for several years and will install on in my next boat. Even considering using one in our camper and just using the built in camper holding tank for urine.
 
Oct 15, 2009
220
catalina 320 Perry Lake
Read the book "Breaking Seas". It is a very entertaing read about a software guy who buys a fixer upper boat to sail around the world. He goes with a composting head and has a hilarious description about how the head worked for he and his female crew.
 
Sep 13, 2013
73
Beneteau Oceanis 41 Seattle
I second that. Don't know if it is real or accurate but it is certainly memorable. I can never see a composting toilet mention without thinking of that book.
 
Oct 2, 2008
1,424
Island Packet 31 Brunswick, Ga
Been reading about composting toilets for use on a boat. Anyone have any experience with one?
Well since you asked, I'll give my opinion. I put a composting head into an O'Day 26. But I had to use the Vbirth, which we used as a storage area, and put it immediately aft and facing aft of the birth. It would not fit in the area built for the Porta potty on that boat. It was not pretty, and I had to keep the entrance to the head area closed, but it work for us.
When we purchased and Moved a board full-time our Island packet 31 she had head issues. I decided to remove all that complicated and smelly gear and install the same composting head in the Island packet. The holding tank on this boat was completely inadequate given the fact that you must flush the pipes out with water or they will soon begin to stink. So when I did the install it opened up the old locker for the holding tank as well as got rid of all that stinky pipe. I did leave the macerator and pump out line in so that I can reinstall the head when we choose to sell the boat.
With that as background let me discuss the composting toilet in particular. First of all, once you get biologically balanced which takes about six weeks, it works beautifully. I certainly would not go back and install a regular toilet. For the nature's head, which we have, it takes a space 23 x 23". And the width is a little tight. 25 inches width would be better. But absolutely not less than 23 x 23. Part of that width involves the elbow for the vent pipe and being able to get your hand down on the side to crank the wheel which mixes the compost after each use. Once it is balanced and as long as you keep the little filter for the vent pipe clean there is almost no odor. In fact I would say no odor when things are working correctly. Certainly much less than we experienced with the traditional sailboat head. The urinal must be emptied daily. We simply pour the urine down the sink drain.. The urine is separated by the toilet from the stool which keeps the compost from stinking. The compost material itself has not been even partially had to be removed over the past several months. Yes that's right several months. The only reason to remove compost periodically is that, as it becomes dense, it becomes more difficult to turn with the crank. I guess almost all of the bulk of the compost is eaten by the bacteria. occasionally i put on gloves, remove a few fistfuls of the compost, put it into a garbage bag and dispose of it in a trashcan. At that time, i will also reach into the corners of the toilet and mix that area. this is necessary because the corners do not get mixed well by the handle. this is the only "gross" part. it doesnt bother me, and there is very little foul odor. mainly just a musty compost smell.
We put the soiled toilet paper into small baggies, and finish our toilet with wet ones diaper wipes. these go into the baggy also, which is put into trash. you can put paper into the toilet, which we do, and it will dissolve, but we don't put all the paper into the toilet.
The only reason I can think of not to use a composting head is the space you need.. It takes more room for a composting head because of the venting and crank than a traditional sailboat head. Best luck! Keith
 

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May 16, 2014
13
Hunter 450cc Miami Beach
Here's my amazon review. I did not receive any discount for my review and have no connection to the company or industry.
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I bought this to replace a Vacuflush on my liveaboard sailboat. I went out on a limb for this quite expensive switch. I am very happy I did.1 month into this process I can say that the composting toilet is the way to go for cruising sailors and liveaboard sailors. there is a nice , mild odor like fresh mulch. I love when I have visitors, I make them stand in the head and take a whiff. you can leave a real stinker and in 5 minutes all you smell is the mulch. It was quite easy to install, the design is spot on. It's a bit tall but a foot stoop of any sort is an easy fix. I am one person on the boat and with 60 to 80 uses per compost change I am looking at about 2 months before I have to empty the thing into a garbage bag. I dump the urine bucket once weekly. there is actually less clean up than with my Vacuflush system. Don't mean to be gross but I would have to use the toilet brush with each use of the Vacuflush. With the composting toilet I simply spritz a little diluted vinegar and that is all. Unless your aim is terrible there will be no wiping (the toilet, that is, you must still wipe your ass) on that note, all I will say is that I highly recommend the natures head composting toilet. I have been living aboard for two years and was either dealing with a holding tank or flushing into the bay. not ideal.Oh an afterthought, I also use far less water. I had previously been dumping about quarter to half gallon per day with the vacuum flush system.
 
May 16, 2014
13
Hunter 450cc Miami Beach
Hi Peggie,
Urine is dumped overboard in the cover of night ! Simply so I don't gross anyone out. I'm in an anchorage that has a virtual river of current with the tide flow. I could see this being an issue in a still harbor.
 
Feb 10, 2004
3,508
Hunter 40.5 Warwick, RI
I have no experience with a composting head, but I have a good friend who installed on his sailboat. I saw it and discussed the operation with him. It's true-ZERO odor! He uses a battery/solar vent to provide the ventilation required. He told me that for him and his wife, they dump the compost about once per month in their regular garbage. I don't remember how often they dump the urine tank. I was impressed.

Imagine: no holding tank pumping every 4 days, no head chemicals to buy, and completely odor free!! I must wonder what the down side is? And why don't manufacturers offer them?
 
Dec 2, 1997
8,119
- - LIttle Rock
Urine is dumped overboard in the cover of night ! Simply so I don't gross anyone out. I'm in an anchorage that has a virtual river of current with the tide flow. I could see this being an issue in a still harbor.
It's still just as illegal as dumping a tank.

Imagine: no holding tank pumping every 4 days, no head chemicals to buy, and completely odor free!! I must wonder what the down side is?
The biggest downside is what to do with excess liquids. 90% of human waste IS liquid...mostly urine, but even solids are about75% liquid. The AirHead separates urine from solid waste…the urine is directed into in gallon jugs (or a tank) You can't legally drain 'em overboard unless you're at sea beyond the “3 mile limit,” so the jugs must be stored and carried off the boat or the tank must be pumped out same as any other tank. And urine alone can stink just as much as solid waste, it's just a different odor. The excess liquids in solids have to be drained off or dried out or you have wet soggy organic material...and wet soggy material doesn't compost. Adding dry material--peat moss is the recommended material 'cuz it breaks down quickly--to each flush helps some, but not enough, and there's usually more liquids than the evaporator--which, btw, requires power--in the self-contained units can handle either. Enough peat moss to keep the thing working during an extended cruise can take up more storage space than a holding tank. Regular doses of a bacteria "digester" is needed to accelerate composting....so you need to keep a supply of that onboard. Composters also need a vent stack... AirHead originally specified a 3” vent but is now claiming that a 1.5” vent is adequate. Continuous power 24/7 to run the evaporator is needed. And composting only works in temperatures above 70 F. Below 70, bacterial activity becomes too slow.
The two most popular "composters" (which aren't true composters, but dessicators) are the AirHead Airhead Toilet and Natures Head Nature's Head Composting Toilets You'll find all the installation operation and maintenance instructions on their websites.
 
Sep 15, 2009
6,242
S2 9.2a Fairhope Al
who's going to empty the damn thing when it gets full :yikes:....not me ....i have enough trouble pumping out my holding tank as it is ...first order of business every monday morning.....then pumping it into the sewer line under the restaurant to empty the tank some days the wind is in my favor others not
 
Jul 1, 2010
868
Seaward 25, Catalina 350 Erie, Pa
I replaced our marine head with a C-head composter this year. Unless the boat grows to a larger boat with much larger tank capacity (mine had a 10 gal tank), I'll never go back.

My 2 cents...the thing just works as designed. The C-head is a simple and practical design. The compost tank is round and there are no hidden corners and crevices for any gross buildup. These things are desiccators, not composters, per se, so drier in the compost area is better (don't picture a wet mulch pile, cause it's not that). I did install a passive vent on mine, but honestly it's probably not even necessary on the C-head. There is no smell. We are using coir, as a media.

Down side, if there is one, is that urine is stored in a 1 gal container, so you either need to dump it daily when in use, or just have a couple more containers available on board for storage. No big deal. I add a splash (a tsp or so) of the Thetford biodegradable blue stuff to the urine container, and there is no urine odor, even when dumping. I dump it into any on shore toilet. If in a remote area, it will get dumped on land. The C-head doesn't have the capacity of the 2 other brands, but it comes with a vented cover for a 5 gal pail. The auxiliary storage pail then is vented in series with the head. You can likely hold about a month's worth of waste by increasing storage this way. What dumps out isn't gross at all...it converts it into dry round waste balls. You could probably use them for ammo, if you wanted (ship cannon not included). So far, I have just brought the compost home and buried it in the yard, but it could just as easily be bagged and dumped in a dumpster.

The ladies have (at least on our boat) had no issues with adjusting to using it. It takes less explanation to visitors than our marine head did, as far as usage directions. For men, they just need to know that they SIT on my boat. You don't sit, you don't pee on our boat.

So far, very happy with the change.
 
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Dec 2, 1997
8,119
- - LIttle Rock
No big deal. I add a splash (a tsp or so) of the Thetford biodegradable blue stuff to the urine container,
You might want find another product, 'cuz you've made the same mistake most people make: assuming "biodegradable" means the same thing as "environmentally friendly." It doesn't....it's a meaningless "feel good" term product mfrs use to deliberately mislead people into believing they mean the same thing.

Nothing Thetford makes is environmentally friendly....but they're all "biodegradable." Believe it or not, formaldehyde, which is the active ingredient in the Thetford "blue stuff" (and also SeaLand TDX) is biodegradable...it just poisons everything it comes in contact with first. Same is true of gluteraldehyde, an even more lethal chemical...Thetford labels that one "non-formaldehyde formula."

The first aid warnings on the label are the best clue...if they say, "harmful or fatal if swallowed, may cause blindness, call poison control immediately," there's nothing "friendly" about it. But if they say something like, "if ingested drink plenty of water, flush eyes for 15 minutes...contact physician IF symptoms develop," it's non-harmful. You may have to try a few to find one that works.
 

SFS

.
Aug 18, 2015
1,972
West Marine Kayak Tampa Bay
A tablespoon of sugar added to the urine container will reduce odors, but having sugar on the boat is a recipe for attracting critters of various types.
 
Apr 25, 2015
282
Oday 26 Oscoda, MI
Very interesting. I was going to throw in a new Jabsco and all new lines but maybe I'll do the C Head instead. Free pump out at the marina however all I hear is nightmares from a normal head system. I like simple and my wife and I will probably only use the head maybe 50 times a complete summer if that. $650 for a C Head isn't bad at all. IMHO
 
Dec 2, 1997
8,119
- - LIttle Rock
At least 90% of sanitation system "nightmares" are self-inflicted by owners who can't be bother to learn how the system works--even that it IS a system--and how to operate and maintain it. It doesn't get any simpler than a basic manual toilet and a tank.
 
Apr 25, 2015
282
Oday 26 Oscoda, MI
Agreed Peggy but even my wife teases me that I'm just trying to go too simple as I get near 60. I would love to have an old truck with the old 4 barrel carb with points and a capacitor. So simple.
 
Jul 1, 2010
868
Seaward 25, Catalina 350 Erie, Pa
I don't wish for those carbs and points again. I remember that era well. Had to have just the right combo of throttle and number of pumps to get that car started in the cold without flooding...you got one shot, and had to get to work on time...stressful.

Kind of reminds me of my jabsco head. We never had any real "nightmares". It worked. I do all my own repairs and understand how it all works, but... we've suffered through the plugged vents, the excess pressure, and the unintended blue geyser when opening the pump out port. Suffered through minor leaks, issues with the pump (requiring rebuuilding / replacement), contorting myself to replace hoses with nice, new $8 a foot Triton ones, yearly winterizing lubing, replacing joker valve, etc. Add to that the fact that a 10 gal tank is just too small, the fact that I could manage to plug it up myself, even though I knew better, stress of having the tank almost full, and knowing you had to find a place to pump out when they were too few and far between. Yea, if my home toilet worked that well, I'd put in an outhouse!

So far, my toilet stress level is way lower with the composter. These things sure aren't for everyone, or every situation, but I"ve kind of bonded to mine.

One disclaimer is that this is our first season with it, so maybe the honeymoon isn't over yet. Time will tell.
 
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