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Re: composting toilet report
Fruit flies, sewer moths, etc, are sometimes a problem with CMTs. Actually there are several types of small flies that can find their way into the collection container. There are several factors that increase the likehood of the problem; location, time of year, ventilation, etc. Screens help but if you are in an area where the are common (like two slips away from the marina dumpster) or if you keep a lot of fresh fruit (particularly fruit with soft or porous skins) onboard, they will eventually find their way into the collection container.
It takes a week to ten days for the eggs to develop into flies. The best remedy is to empty and clean out the collection container as soon as you see them. This is the downside to CMTs that hold a large amount of waste. Just emptying the container won't get rid of the eggs. Some brands, you can put a fly trap inside the housing and some brands you can empty the collection container and then tie to a line and submerge it overboard for an hour or so or else just hose it off on the dock if you are in a more secluded area. You will get some residual waste in the water, but no more than the pump out hose does when they purge the line by dropping it in the water after pumping out the holding tank.
I have only had a fly infestation on board one time during the year we used our CMT (I have used it ashore for an additional year now for research). I neglected to empty the collection container before we went ashore for several weeks because of my back problems. It is not a big problem, everywhere, all the time and it can be controlled.
If you are in an area where flies are a problem, you can mix diatomacious earth with your medium and it will kill any larva. It works mechanically, not chemically. It is non-toxic to humans and you can get it at garden supply stores. Another advantage of emptying the collection container every week is that with some systems, you may not need to ventilate the collection container. You will use more medium, but peat moss is cheap and may be worth the trade off if venting the system is problematic. Some people have said that the peat moss was infested with fly larva. That is possible I guess but I suspect the came in from the outside. If you consistantly get flies from the same batch of peat moss, buy some new or else use sawdust. Cypress sawdust is the best in my opinion because it holds a lot of moisture, but is can be hard to find.
Last edited by fireboat52; 06-07-2012 at 11:09 AM.
Reason: grammer and explanation