Black soilder flies in my composting toilet EEEEK!!

Hey all, we have a sun mar excel. We've had it for years and a month ago we took the unit out to clean it and start over( hosed down the toilet and scrubbed it with baking soda) we have NEVER NEVER HAD THIS ISSUE!!! But now we have black soilder fly larvea and black soilder flies starting to make an appearance. so yeah super gross I nor do anyone else in the house want these little pesties flying round our netherbits. The only things enjoying it are the chickens who profit from the larvea that are swept up. They are not inside the drum at this time but seem to be isolated to the evaporation chamber. However I feel it is only a matter of time if we don't nip it in the bud. Please any advice would be appreciated. TIA.

Well, i really have no idea, but is it possible that cleaning the unit actually caused other organisms to die back, and left a niche open for the flies to proliferate?

For example, in some forum discussion about chicken coops and deep litter, I heard someone say that they used to have more diseases when they would try to keep their chicken coop regularly emptied and periodically cleaned it out and scrubbed it. And then when they went for deep litter the diseases cleared up: they kept a deep layer of leaves in there, adding to it for a year or so, and never removing the entire amount of litter.

But I have no suggestions for a remedy, I'm sorry.

There's this thing inside me that wants to see pictures....is that weird?

Dora, welcome to the Back To Nature world of the composting toilet! If it isn't fly larvae, it's gnat larvae, especially in the summer. There are a lot of insects in nature that break down all the animal waste on the ground and they know how to find it.

I'm really sorry to say, but it is a constant job. Fly and gnat larvae can be in the mowed weeds if you use that for the covering layers, they can be in house plant soil, or they can just sneak in the door.

I keep sticky fly paper hanging nearby and it catches whatever comes out of there. Sometimes it's surprising how many there are, even when there's no sign of them elsewhere.

I don't compost in the toilet. I put a sub container in the toilet and empty it every 4 days in the summer, compost it outside. Then there isn't time for the larvae to hatch.

One thing I am trying, and I don't have reliable results yet, is baking soda sprinkled over solids immediately, then covered with mowed weeds or sawdust. Then to counteract the alkalinity of the baking soda, I add an equal amount of mowed weeds to the toilet amount, which will add some acidity of their own.

The reason I am trying baking soda is that in my tall grass at my rural place there are little bugs that I get itchy bites around my ankles in the summer, even when I wear rubber boots. So I put baking soda in the boots, which is nice for a lot of reasons, and it seems to stop tiny bugs that get into the boots. So I am hoping that it works in the composting toilet, too. I would say so far there's less than usual, but they are not completely gone. I may have to up the sprinkle of baking soda. If that makes a big difference, then I'll have to do more to add acidity back into the outdoor composting toilet container.

Ooh, Cristo, are you sure baking soda is a good idea in your compost? The first thing that comes to my mind is that could build up a lot of sodium, which doesn't sound like a good thing.

Right, Rebecca, that's what I meant by the alkalinity part of that. It's an experiment. But this is not the main compost, this is a much smaller amount of compost that there's already coffee grounds and acidic weeds in, and the baking soda is a very small part.

I've tried those peppermint sprays, herbal things, they don't do it. Other than giving flies and gnats a vent to leave by, and sealing the seat area, I don't know how else to get them out of there using an organic approach.

It's not just the alkalinity. Even if you neutralise the alkalinity with an acidic ingredient, sodium is an element and will mostly stay in the compost. It's necessary in tiny amounts but people generally advise avoiding sodium in growing soil.

Okay, here's an idea about flies.

I saw a light-based fly trap for composting toilets in a book or website. We tried it and had some success. Caught some flies but not all of them. You attach a clear bottle on the outside of the composting chamber in a location where light will fall on it; flies go into and most of them don't go back out into the composting chamber. Look it up to get the funnel idea, but basically it works on the idea that flies are attracted to light. ONe example is at the bottom here:
http://www.omick.net/composting_toilets/barrel_toilet_construction_manual.htm
But if you google "fly trap" bottle "composting toilet" you'll find several.

For the past year we've been using a sticky window trap for flies in our kitchen, which works GREAT! Remember the sticky spiral fly papers that hung in kitchens? This is a flat clear rectangle that you stick on the window where sun falls on it, and when flies bumble against the window towards the light, they get stuck. It is disposable plastic but pretty small and extremely effective. It's easily available in the US, eg on amazon. I've been using the Blag Flag brand, which says it doesn't have insecticide, just stickiness.

Both of these only work for types of flies that are attracted to light, like common houseflies.

I've been thinking that maybe a translucent hinged window in the side or door of the composting chamber would work well. You could stick one of the clear window traps on the inside surface and keep it shut, and all the flies would get stuck to it. You'd have to position the hinged door in a place where it wouldn't get fouled or splashed. I think it would work spectacularly. But perhaps one wants to be sure not to catch crawlies that don't fly, that politely stay down in the manure and do their thing. So the hinged window would have to be big enough to have a couple inches of very smooth surface on all four sides of the sticky trap, to stop crawlers.