ELI5: How do compost toilets work

[Virginia Lee]

Our 1978 boat was not plumbed for a holding tank, so the composting toilet was the obvious choice to make her legal. We have had fruit flies twice in about 3 years time. Once the fan failed (battery problem) - so I can understand that. This last time it was just that the toilet was not sealed firmly. Each time I tried diatomacious earth - no luck. If DE gets wet, it won't work, so sprinkling it on the solids is not going to do the trick. I tried putting a nice pile on top of some coffee filters, and left it for a month. No luck - tons of fruit flies. So, then one has to take it off the boat, take it home and thoroughly clean it out. Since it's had a month to decompose, it shouldn't be too disgusting. The worst experience was when there was too much water in the solids container and it went anerobic. That was disgusting. But ... I never have an odor problem, and on the prior boat with a holding tank, I frequently did. And the pump out at my marina is non-functional more than half of the time, once for over a year. (What can I say, it's a Miami Dade County facility!)

[wrwakefield]

Originally Posted by lindabarzini

(Explain like I am 5)

How do these compost toilets that are self-contained work? What about odor? Are these considered an upgrade from a jabsco marine head?

I can't see dumping and rinsing the bottom receptacle. Do people just purchase several empties?

Hi Linda,

We replaced one of our Lavacs with a Nature's Head last year. Works great. No odors. No bugs. Guests prefer it over the other Lavac head '...because we don't have to pump it...'

We may put in a second one...

Here is a good video by a land cruising couple using one in their RV. It will explain why emptying is no big deal... just another chore, and not as frequent [or risky...] as finding facilities to pump out a holding tank...

Nature's Head

They have several other videos as well, depending upon how much you want to learn...

You will find many discussions on this forum regarding 'composting toilets' [desiccating, really...] It is important to pay attention to feedback from those of us with first-hand experience with one of the following urine separating units: [Nature's Head; Airhead; C Head; and Separett. [I believe these are all the brands with liquid separation that could go on a boat...]


In case this is helpful.

Cheers!

Bill

[Canibul]

We replaced both Baby Blake marine toilets on our old boat with Nature's Head's. We're converts.

After removing the disintegrating yet half full 30 gallon tank, hoses, pumps, fittings etc. from the previous system, I never want to share my living space with another marine head setup.

Hardest part for me personally was adjusting to peeing while sitting down. Emptying the thing is a real non-issue. The odor is as reported, smells like potting soil. Looks like it, too. Not really anywhere near the gross-out one might expect.

And we finally got rid of that smell in the hull.

[Minggat]

Virginia Lee,

I have heard some horror stories about units that really do try to compost. Yours sounds....bad... I think it might be helpful if you mentioned who made yours.

Aside from that, there seems to be some many keystrokes devoted to what to do with the waste.

Urine is sterile. It goes overboard.

The solids only get more solid as they dehydrate. When I am not in open water, they get the same treatment as what we do with the droppings of our pets that we are required to be responsible for. They are basically dirt clods at that point.

Each male aboard Minggat get their own empty liquid laundry detergent bottle to relieve them selves into. These are so easy to come by. Go visit a laundromat. No male would ever think to try and stand to urinate in the toilet. He would be Keelhauled.

Since the females are the ones who primarily fill the bottle on the toilet, I instruct them that they are responsible for emptying it. That's how the urine got dumped in the solids bin in my earlier post. I learned something there.

C-head uses a standard 1 gallon water or milk bottle for the urine collector. Got an issue with that bottle? Get another one. So way simple.

[Scout 30]

We went with the C-head because it fit our space perfectly & the crank is on the top instead of the side which we don't have room for. Doesn't hurt that it's less expensive either. The C-heads don't have to be vented & ours isn't but we haven't been through a summer with it yet. I spoke with another Scout owner that has had a C-head for quite a while without venting it & he said it's not a problem. The C-head also comes with a special vented top that fits a 5 gallon bucket for storage.
C-Head portable composting toilet system

https://www.youtube.com/watch?v=zJtWnM3I2Io

https://www.youtube.com/watch?v=gcMKnjYUTUY

[Mike OReilly]

I think everyone has pretty much covered it. We have a Nature's Head which replaced a perfectly functioning Skipper's Head II. As othes have said, they're more accurately called dessicators than composters, although left long enough they will compost. Venting and dry material is important. And yes, coir is a better choice vs peat.

After five years of seasonal full-time use I feel this is one of the best upgrades we have made to our cruising boat.


Why go fast, when you can go slow

[captlloyd]

Originally Posted by Canibul

We replaced both Baby Blake marine toilets on our old boat with Nature's Head's. We're converts.

After removing the disintegrating yet half full 30 gallon tank, hoses, pumps, fittings etc. from the previous system, I never want to share my living space with another marine head setup.

Hardest part for me personally was adjusting to peeing while sitting down. Emptying the thing is a real non-issue. The odor is as reported, smells like potting soil. Looks like it, too. Not really anywhere near the gross-out one might expect.

And we finally got rid of that smell in the hull.

You bring up an interesting point. Next time you go by a ''Porta-Potty'', peek inside and note how they handle the urinal part of the set-up. In this situation the urine is going in with the rest of the waste. Not what you want with a composter. However it would be easy to divert the urine into your composter urine catching system. Another words, a set-up that would allow males to stand-up while urinating. Do it with PVC. I am thinking of building a boat and if I do, this is how I will set it up.
I believe composters are the way to go.

[Sailorbob8599]

Originally Posted by lindabarzini

... (Explain like I am 5)

How do these compost toilets that are self-contained work? What about odor? Are these considered an upgrade from a jabsco marine head?

I can't see dumping and rinsing the bottom receptacle. Do people just purchase several empties?

You did say to ... Explain like I am 5 so here goes ...

I hear tell they don't work at all until you crap in them!!!

[AD28]

real sailors don't stand up to pee, anyway...

[Simply Sailing]

Originally Posted by boatster

Do composting heads have to be vented or can they be self-contained like a porta potty?

The purpose of venting the composting heads is to aid in dessication which helps healthy "good" bacteria grow and inhibits the growth of "bad" or stinky bacteria. A composting toilet WILL work without being vented, but you will have to change the solids container more often because the contents will not compost as quickly as it will with a fan/ventilation. You are also more likely to have an issue with smell if there is no air flow. That's not a certainty, but it may happen and it will NOT happen (regardless of what some naysayers who don't have composting toilets may say) with a fan/vent. We've had an Air Head for 6 years and love it. But it is installed properly, with the included fan.

[Simply Sailing]

Originally Posted by AD28

real sailors don't stand up to pee, anyway...

Amen!

[dkroar]

We have a Nature's Head, and it works great, but I need some advice from a female's perspective. Are there any females out there who could privately PM me so I could ask a couple of questions? Thanks in advance.

[Steve Bean]

For ideas on making your own desiccating toilet, go to Sailfar.net forum and search for: the $10-20 or even free composting toilet.

[alansmith]

You see guys going through all sorts of modifications so that their toilets don't stink. Watched a video just last night of what a guy did on a large cat to get fresh water to his flusher. He had two. Electrical mods, valves, new pumps, t's....wow....


I do like the two ideas presented during this thread of plumbing the urine to a holding tank and making some sort of stand up (maybe like they do at port-a-Johnny u would use at a concert) piping modification.

[Cthoops]

Originally Posted by dkroar

We have a Nature's Head, and it works great, but I need some advice from a female's perspective. Are there any females out there who could privately PM me so I could ask a couple of questions? Thanks in advance.

PM sent.