I installed the Nature’s Head after having an unfortunate experience last year with an over filled holding tank (a very messy version of Old Faithful was the odorous result). I had considered making a home-brew version (off the shelf parts would be sweet); but my time is not unlimited and I had other things to spend it on (rewiring the boat, for starters). The boat show price was high; but not unreasonably so.
With me and my gal, the two plus gallon liquids container generally needs emptying every other day. I do have a spare jug which I feel is mandatory and should come standard. I will soon be making a custom fit bracket to snugly hold the spare jug to the bulkhead to reduce the risk of it going flying and spilling the contents all over the interior (a horrifying thought).
The solids container does seem to last quite awhile; but I’m not convinced it makes the advertised 60-80 uses. Of course, if putting the toilet paper in the head (and it is somewhat distasteful to put it anywhere else), it will fill up much faster. The TP takes some time to break down. The poop does become inoffensive in a couple of days, although it surely takes much longer to fully compost than the practical time it can remain in the toilet. There is rarely a smell (the cat box is much more of an issue). The small fan barely registers on the amp meter and does an admirable job of venting to the anchor locker.
Dumping:
From a philosophical point of view, I think that discreetly pouring pee overboard is not much of a health risk anyplace that is not unusually sensitive and not morally shaky, unless it done in a really crowded harbor at which point it is bad manners. Legally is a different thing altogether, and I’m pretty certain it is universally frowned upon by those men with shiny badges. You makes your choices and you takes your chances. It should be easy enough to find a shore side facility every two or three days, although I can think of more pleasant things than carrying around a couple of gallons of smelly pee.
By the same token, I think that putting partially composted solid waste in a thick contractors trash bag (the Nature’s Head site suggests a regular kitchen garbage bag…given the subject matter I think I prefer the extra toughness of the thick bags) and putting it into the dumpster is no more offensive or generally harmful to mankind than disposing of dirty baby diapers in the trash; but it may still be illegal. The Nature’s Head folks suggest it is dirt at this point (assuming some time between last deposit); but I am not certain that it really, truly qualifies without having at least months of time to cook. Choices. Chances. I read somewhere (the c-head homepage, perhaps) that sealing it in a pickle bucket (aka Home Depot ‘Homer’ bucket) with some bleach qualifies it as “treated” and it suddenly becomes legal for about the same price as a pump out. I’m not sure; but it sounds like a reasonable compromise assuming an offshore dump is not practical. I emptied mine after using it occasionally all summer plus regularly for a ten day trip for two. It was not anymore distasteful than a pump out, and more pleasant than dealing with a porta-potti. I expect the next time I empty it will be when I recommission the boat next spring. Although I’m now living aboard part-time, so that estimate might not hold true in the end.
The bottom line:
Everything in life is a compromise. But as far as compromises go, this one ain’t that bad. And I no longer have nightmares of exploding holding tanks. Bonus: By pulling the holding tank, I now have room for a new water tank to augment the somewhat anemic twenty gallons of the primary tank. If only I can find an off the shelf tank that would properly fit…