Composting Head for Liveaboards ?

[pcmm]

We've got a C-head aboard ( and are ordering a second one) the C-head has a large list of "media" for the solids tank. We're currently using cedar hamster bedding as the media and it works great. The C-head has a major advantage over the other "heads" in that the agitator actually agitates all the media. the natures head and air head leave a large area "untouched" when you crank the handle.

The C-head has worked great for our last 2 week outing as a family of 4. every once in a while we just empty the solids tank into another 5 gallon bucket that is lined with a garbage bag. then just seal up the bag and put it in the dumpster. It s great and effective system.

[NevisDog]

Originally Posted by Reiheld

One more thought: is/was your composting head ventilated? ...

I take it this question is about my sad experience - thanks for attempting to uncover the reasons for our solids turning to cement. As I've said, we decided not to continue with composting heads and have taken a more conventional route. To answer the specifics:
- we used solar power to run the fan that comes with the AirHead toilet. Ventilation of these units is excellent IMO, there being no odours, not ever, and expelling the ventilated air was also no problem, the unit being installed in our caravan ashore while we trialled the concept.
- we first trialled sawdust; when that proved useless we asked around and were told, by two individuals who had experience of composting, to use wood shavings as this would allow better aeration. Even when we filled the container more than half full of shavings, we still managed to generate concrete, which adhered strongly to the stirring mechanism whenever we came to empty it.
- we did not try coir or peat or moss; of course that should have been our next trial but we wanted an economical as well as practical solution; the comparative ease of emptying a portable (liquid filled) toilet seemed like a simpler and cheaper option.
- we never allowed urine to contaminate the solids compartment; only my wife and I used it and we were very particular about sitting and being scrupulously careful in this regard.
- the shavings we used were of NZ beech (= European birch?) a softwood, untreated timber. I have no idea why this mixture should turn to cement instead of drying out.
Finally, the biggest problem, we finally realised, was not being able to store the compost for twelve months while it breaks down - the mixture must be disposed of each month and I seriously doubt it can ever be described as compost, being simply un-composted muck; I'm certain not even the fish will distinguish any improvement over a simple flush sea-toilet.
Thanks for trying to identify the cause of our failure. Since others have succeeded where we failed, it is clear to me we did something wrong but I'm still unsure of exactly what we did that was so dreadfully wrong. I'm not blaming AirHead at all - the toilet is well built - but I do want others to be aware of our experience and hopefully avoid a repetition if a clear explanation can be found for our failure.

[NevisDog]

Originally Posted by pcmm

... The C-head has a major advantage over the other "heads" in that the agitator actually agitates all the media. the natures head and air head leave a large area "untouched" when you crank the handle.

I think this may be a significant fault with some toilets. It seems to me that any un-agitated volume is simply wasted space.

[Mike OReilly]

I've never used a CH so don't know about the quality of agitation. Could be right. We sometimes end up with material tucked into corners. I keep a garden trowel nearby to deal with that when it happens.

But I also wonder about the whole wood chip usage. I don't know any NH or AH users who use this material. It's certainly not recommended, and I really don't think it would work very well over the four to six weeks these two heads are designed to operate between dumps. I wonder if part of the success CH owners have with wood chips is b/c the dump frequency is about twice as fast. Perhaps the material doesn't have time to absorb and congeal?

[pcmm]

Originally Posted by Mike OReilly

I've never used a CH so don't know about the quality of agitation. Could be right. We sometimes end up with material tucked into corners. I keep a garden trowel nearby to deal with that when it happens.

But I also wonder about the whole wood chip usage. I don't know any NH or AH users who use this material. It's certainly not recommended, and I really don't think it would work very well over the four to six weeks these two heads are designed to operate between dumps. I wonder if part of the success CH owners have with wood chips is b/c the dump frequency is about twice as fast. Perhaps the material doesn't have time to absorb and congeal?

The C-Head "bucket is actually that, a 3 gallon HomeDepot type bucket and the agitator is oriented so that the blade at the bottom "sweeps" the whole radius of the bucket. Its a very simple and efficient design, much better than the others that are simply bent up rod.

I don't think I would wait 4- 6 weeks between dumps either. If I remember for the NH and AH the recommended interval is when the handle starts to get hard to turn ( which is a bit vague!) with the C-head I dump every couple of weeks because its much more "fun" to dump when the bucket is only half full vs full full!!

[Mike OReilly]

Originally Posted by pcmm

I don't think I would wait 4- 6 weeks between dumps either. If I remember for the NH and AH the recommended interval is when the handle starts to get hard to turn ( which is a bit vague!) with the C-head I dump every couple of weeks because its much more "fun" to dump when the bucket is only half full vs full full!!

For us, and other NH/AH users here, this mostly comes out to between four to six weeks. This is for two adults, full time usage.

I could dump more often, but that would kinda defeat one of the benefits of these heads. The smaller holding tanks is the main reason I didn't consider the CH, but it certainly is right for some users. Like I've said, I prefer CH's use of non-proprietary vessels, and I think the aesthetics are superior. But for me, I prefer the longer gaps between dumps. It gives me a greater margin of error, so to speak, in cases where dumping is inconvenient ... I can usually squeak another week or so out of the system.

[ReMetau]

Composting boat heads aren't really composting heads for liveaboards unless you can leave your bucket for weeks so that they can actually compost. They should call them for what they are, poo in a bucket with some moss.

[Blue Crab]

Peat N Poo Pail?

[Reiheld]

The C-Head guy prefers to call them 'mouldering heads.' As pointed out, true composting takes quite a while, longer than these buckets provide. Be that as it may, the poo is dried, well-coated with the fibrous medium. The thing that those who praise the larger-capacity primary containers seem to miss is that C-H comes with a ventilated secondary container, a 5-gallon bucket, into which the used fiber and lumps are dumped for further decomposition. It extends the time between necessary port calls for many weeks, and depending on technique and users, maybe months. (We are only two, usually, and do a light catbox scooping of the primary bucket when indicated. This requires less frequent fiber replacement, and fills the secondary bucket much more slowly.) The engineering of this head makes the poop-scooping a two-minute non-issue, as the primary container lifts out easily, one-handed, with no disassembly or corner-scraping required. And as noted, the gallon pee jugs are free. Yep, I remain pleased, especially when I motor on past the queue at the town pumpout on a summer Sunday afternoon.

[Mike OReilly]

Originally Posted by ReMetau

Composting boat heads aren't really composting heads for liveaboards unless you can leave your bucket for weeks so that they can actually compost. They should call them for what they are, poo in a bucket with some moss.

As has often been said, these are really better called desiccating heads. Complete composting takes longer. As for your second statement, all I can say is you are flat out wrong. These heads, properly used, are the best heads for cruising couples. There are so many advantages over a standard marine head: simplicity, safety, no cruising time limits due to full holding tanks, huge recovered space on the boat ...

I don't know why some people insist on trying to denigrate these heads with references to poo in a bucket. Standard holding tanks are just toxic poo slurry in a tank.

[smj]

We use a combination of coir and cedar shavings in our C head. The coir covers and dries the deposits and the cedar ads a nice smell of the forest as you sit contemplating life. We dump the solids in the Chead every week as compared to every 4 weeks with the Nhead and Ahead. We found we never had to adjust or ad coir to the Chead as we would the other 2. Love them all.

[NevisDog]

Originally Posted by Mike OReilly

As has often been said, these are really better called desiccating heads. ... I don't know why some people insist on trying to denigrate these heads..

Well, if by denigrating them we get all this useful info on how to use them properly then ... please continue. I can sure see the advantages, now I've sold my AHead if only I'd asked questions earlier.

[Mike OReilly]

Originally Posted by NevisDog

Well, if by denigrating them we get all this useful info on how to use them properly then ... please continue. I can sure see the advantages, now I've sold my AHead if only I'd asked questions earlier.

Yes, some excellent info here. We've now learned that NH/AH should not use wood fibre exclusively. Although it sounds like CH users can do so.

And sorry for my expression of annoyance earlier, but I get tired of people making definitive statements about things they clearly have little or no experience with. Composting (desiccating) heads seems to be one of those topics.

[daleshupe]

I've just purchased and in the process of installing an AH in my sailboat. I am considering using the old pump-out deck penetration for the holding tank for my venting system, but I'm not sure what kind of cowling to put over the top. I don't want water coming into the system if I take a wave on deck or when I wash down the boat. Also the vent would be pretty close to the cockpit, so worried about smell. Any suggestions? I really don't want to run it aft or make a new hole in the deck if I can avoid it.

[Mike OReilly]

Originally Posted by daleshupe

I've just purchased and in the process of installing an AH in my sailboat. I am considering using the old pump-out deck penetration for the holding tank for my venting system, but I'm not sure what kind of cowling to put over the top. I don't want water coming into the system if I take a wave on deck or when I wash down the boat. Also the vent would be pretty close to the cockpit, so worried about smell. Any suggestions? I really don't want to run it aft or make a new hole in the deck if I can avoid it.

I ran our vent hose though the old deck pump out fitting just as you plan. I fitted a mushroom vent for the cap which I can screw closed in the event of impending green seas. So far I've had no problem, although success may depend on deck layout and how wet your deck normally is.

Only smell you should get out of it is an earthy musty one; like rich soil. You might get a bad odour immediately after a use, but if it doesn't dissipate almost immediately then something is wrong with your mix.