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I'm looking to put an "air head" composting toilet and a shower in "Pai Nai" aka "Pumpkin".  I'm planning on using the standard location in the main cabin and and I can't find much about it online.  I would appreciate any feedback or links on this....Toilets, through holes vs pump, interior paint/sealant, location, etc. 

Thanks for your input, Rob

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In tikirio our toilet ...

I would vehemently suggest against any small composting toilet (regardless of manufacturer) on any boat. They are not suitable for anything more than a couple of deposits per week, and that can be pushing it. I have been the recipient of vast sums of money for the service of replacing composting toilets on small boats with more typical sea heads (especially the Lavac as suggested by Chuck.) The Lavac is not well suited to use with smallish holding tanks since the pump draws and discharges a significant amount of water. I have only clogged a Lavac once in over 6-years of daily use, and that was because a child input a foreign object.

I have used Marelon thru-hulls and seacocks since the early '90's and never had a failure. If you use quality hose and fittings, the service life of modern sea head is likely longer than a Yanmar diesel engine, and with far less maintenance.

We use Behr Premium Exterior Semi-gloss (from Home Depot) latex paint. It has great wear, dries smooth (when applied properly), and provides a great breathable waterproof barrier.

Sealants depend on the application, so advice is impossible here.

Hi all,

I would beg to disagree on others' opinions of composting toilets on board.  We have had an Airhead composting toilet on our Tiki 38 Lipa Lipa for the past 10 years.  It is in the forward port side cabin (we went with "option 2" for the layout from the original plans).  We have been very happy with its performance.  It can handle full time use of 2 or 3 for several weeks.  We don't have any problems with it smelling.  There are no through hulls, and it is completely legal to use anywhere as it doesn't pump out.  The liquid container tends to get smelly well before the solids section, which for our toilet hardly smells.  The trick is to put sugar, or similar, in there - this discourages the type of bacteria that make smells.  We use cheap lemon cordial - each time we empty the liquids, we put an inch or so of this in the bottom for the next round.  To be truthful, if we are in an anchorage, we use the deck hatch or wee overboard, but the toilet is always there if you need to hide away to go to the loo.  The solids can be emptied into another container, after about 4-6 weeks, then either emptied overboard, or buried in a friend's garden.  It turns into an earthy-smelling powder.  It definitely composts well - maybe it's the heat of the tropics in all the areas where we have used it.

All the best,


bucket and chuckit... works well for me.. porta potty for the ladies

I had two buckets, a black one for the gents and pink for the ladies...  You have to maintain some sort of decorum.  Best only invite ladies with a good sense of humour though  ;-)

steve martland said:

bucket and chuckit... works well for me.. porta potty for the ladies

Hi Guys,

We, of course, apply "bucket and chuck it" in suitable locations as well, to reduce the amount we're putting into the toilet and lengthen times between emptying.   Better still, we have a very suitable deck hatch as a outdoor toilet when we're all good friends on board. However, it's great to have the option not to chuck stuff overboard….  if you're in a beautiful, clear anchorage and fancy a bit of snorkelling, you are better off not having your …ahem… "solids" floating in it(or anyone else's, for that matter).  The advantage of the composter over a portapotti is no need for any fresh water, and also the lack of chemicals (and associated smell) - when you do empty your toilet and throw things overboard well offshore, you are not throwing formalin in as well.  


Emma, Lipa Lipa

I'm considering the Nature's Head. I have read countless reviews and the comments above mirror those reviews exactly. Some say it works great and some say it doesn't compost. I'm wondering if the differing results are from the those who use or don't use the 12v fan option. It sounds like that could make all the difference. But i could be wrong. I'd love to hear from those who have posted if this theory is accurate. Thanks for all the great info :)

PS: I realize that actual composting takes months up to a year even and that these heads actually are dehydrating the poo and starting the process for composting... just to be clear :)


Hi Brandon.  The Airhead has a 12V fan as standard, so maybe this is part of the solution - this draws a very small current, and is on all the time.  It also has a tumbler in the solids tank, so you give it a tumble each time you make a deposit, this introduces oxygen, which is an essential part of the composting equation.  The automatic separation of solids and liquids is an important part of the design - if urine is mixed with the poo, then the process would need to be much longer, and you would need a huge tank (more like a domestic household composting toilet).  However, I don't agree that the process is dehydration rather than composting - in our Airhead, it is a moist process, and definitely composting.  If you leave it alone and don't use it, it then goes powdery.  Once the composting is working well, all the bugs are really fast, you make the deposit, cover it with the other compost, and the poo is almost instantly turned to compost.  No smell at all!  You need to use a bit of peat moss to get things going, but once it's working well, you just cover the fresh deposit with the compost that is already there, using the tumbler.



Hey guys,

Just to wade in on a subject about which I have absolutely no clue, other than 'urine removal', 'fecal agitation' and 'blowing hot air' of course, here are some thoughts to ponder.

Now, it seems to me there is a secret to these magical Midas devices that takes something that is not so good and turns it into something that is quite desirable,... if the garden needs food.

The secret may be in the character of the situation into which the device is fitted.

You see, around most of the places that I find myself there is always someone ready to 'take the p!$$' or 'stir the s#!t' and this may be the vital ingredient to this conundrum of why it works well for some and not so much for others.

Most mornings I awake in quite a stumbley manner and fumble with the coffee pot to create the magic brew that removes said stumbles and apparently this is always a funny event as Casey consistently conducts urine removal for me.

Upon entering my In-laws house there is usually something silly going on which allows me to engage with fecal agitation.

And being back in Santa Fe, NM, the City Differente, there is an abundance of air being blown up some Khyber Pass,... I suppose the wiring would have to be reversed for that last one.

Anyway, as one can see, the situational character may play an important role in how these devices work. When we eventually find ourselves on a largish boat I think we will definitely being giving one a run for its money.


When you are ready to sell let me know... So how much does a used, non working natures head go for these days? ;)


I can wait... No rush
Hey there Chuck,

Rereading my attempt at humor this morning I see barbs I did not see yesterday. There was absolutely no intention of being insulting just playing on words,... I apologize matey.

You are quite correct on the peat moss not being Eco-friendly, I wonder if, based on the fact that it is decomposition that produces the bacteria that breaks down the solid waste in the bowl, veggie waste might work. My folks have a composting bin in the back yard that gets their scraps and never produces foul odors and the process seems the same. The scraps from the food that produces the solids from us may provide the same benefit as a peat moss in the bowl.

Again, I apologize for not thinking.

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