Originally Posted by Yobarnacle
I considered a composting head.
You have to have a supply peat moss or wood chips to scatter over the feces. On smaller vessels, this means more bulk supplies to stow. Composting toilets use a small vent fan and a heater to dry the effluent. Battery drain. Also, they separate the urine from the solids, so the urine bottle needs frequent dumping. Kinda like a porta potty.
The best in my estimation, is the tried and true marine head and holding tank, with a lockable Y valve and pump to dischage overboard where legal.
Good ventilation to holding tank eliminates odor.
Don't put oil in your toilet, as some recommend.
Aerobic bacteria doesn't cause stink.
Seal the holding tank contents with an oil film, and you only have anaerobic bacteria, which creates the foul odor.
Since the Nature's Head, Air Head and C-head toilets separate the solids from the urine, they don't need to dry anything and shouldn't require a heater -- unless your loo regularly drops below freezing. Ain't gonna happen on the desert lakes I plan to be roaming.
If you feel you need a vent fan, a small day/night solar fan is plenty big enough for the C-head, and probably for the other two also.
Coconut coir comes in highly compressed bricks. A stash of it would take up considerably less space than the typical holding tank does.
You're right about the urine bottle; I'll deal with it. It helps that the C-Head uses standard one-gallon plastic jugs, so you can store a couple of full ones for a bit if you need to. And you don't need to pay $40.00+ for each spare...
Remember that I'm not going blue water cruising in my boat; I intend to putt around some inland lakes for a few days at a time max. Then I'll trailer it back. Unless the wife throws me out for building it, of course; in which case I may want to finish it in a hurry.
sorry folks, didn't mean to hijack the thread and turn it into one about composting toilets. I'll let the forum know what I think of the C-Head, after I've had it in my motor home for a while.