Reading about people’s frustration at eliminating flies (which I hate with a passion) is actually affecting me (I have ptsd). I use a hose attachment and haven’t had any problems since. Only a small quantity is required and is safe for the worms. I imagine it’s actually beneficial for their digestion since its like little microscopic scrubbers passing through their systems.

I ended up cleaning out and restarting my entire system this past week. I’m glad I did…there were probably millions of gnats completely worked through the system. I now know what gnat larvae look like. Pretty gross! It’s strange because I think the baby red worms are cute, but I guess the white larvae look too much like maggots to be cute.

The weather was very nice last Saturday, so I took the whole Worm Inn outside in front of our apartment building, put on a pair of rubber gloves, and started sorting worms from everything else. I was able to save over 100 of them, along with a couple of cocoons. I didn’t have the stomach to carefully sort through and get all of them out because the abundance of gnats and larvae was grossing me out too much.

One note I should add here is that the Worm Inn really is amazing at giving worms enough oxygen but also keeping a moist, healthy layer for them to thrive in. To try to starve out the gnats, I hadn’t fed or watered the worms for probably more than a month by the time I cleaned out the system, and in the winter time our storage room can get quite cold, but the worms were still doing great in there! They didn’t seem bothered at all by the gnats, the lack of food and water, or the cold. I found plenty of baby worms and cocoons. They are very resilient creatures!

I put the worms I saved into a plastic tupperware container, along with a small amount of compost, bedding, etc. from the old system to keep them alive but not so much that it would attract the gnats again. I read online that adult gnats can survive for about a week, so I decided to keep the worms in the little box with a large air hole poked into the top for 6 days to give time for any wandering gnats in our apartment to die out before I set up the Worm Inn again. The worms really hated being in the box, and I lost about 15 of them over the course of the 6 days. They decided to venture out and try their prospects in the corners of our storage room, but unfortunately, that didn’t work out so well for them. Luckily, most of them were smart and stayed in the moist box.

I dumped out the leftover infested parts of the system under the bushes in front of our apartment building (probably not something I’d recommend in the US or Canada, but in China, nobody seems to mind that kind of thing). Then I washed the Worm Inn itself, first in the bathtub to rinse out as much of the dried up compost as I could and then 2 times through the washing machine. There were gnats worked into every nook and cranny of the Worm Inn, so I really wanted to make sure they were all dead before restarting. I hung up the Worm Inn to dry, and after a day or two when it was dry, I put it in the freezer. (Overkill maybe, but I really don’t want another infestation after all this!) I left the empty Worm Inn in the freezer for about 3 days.

On the 6th day, after we hadn’t seen any gnats flying around the apartment, I finally got the system going again. I started with shredded cardboard and some frozen “smoothies” of the scraps from my freezer. I covered the scraps with more cardboard.

Then before adding the worms to the system, I hand rinsed each one of them in the bathroom sink to make sure any microscopic gnat eggs would be washed off before restarting the system. When I started to wash off the worms, I noticed that a few gnat larvae had crawled to the top of the tupperware box and died, so I think it was definitely a good idea that I rinsed off the worms and didn’t just add them into the Worm Inn with any of the old compost materials.

The new, clean Worm Inn has been going for a couple of days now and so far I haven’t spotted any gnats or roaming worms, so things seem to be going well.

In the spirit of Bently, i.e. experiments, why not split the two populations? Have one clean one, and the other all gnaty?

But on the subject of clean, does anyone have any experience recycling/restarting an infested system? I use three white plates and chopsticks, so i’m sure someone has a more efficient method!

I also tried some peppermint oil and clove oil after reading a comment about that on one of Bentley’s other posts. First, I left a cotton ball on the top of the Worm Inn for a few days…no noticeable affect on the gnats. Yesterday, I tried pouring some of the oils into a little cup and resting that on the top of my cardboard layer inside the Worm Inn. Maybe about 10 gnats were dead in the cup this morning, but that is a tiny drop compared to the total number of gnats still happily flying around the top part of the Inn.

At this point, I think restarting the Inn and washing it out is going to be my best bet to quickly get rid of of the gnats. I’d like to get some compost ready for my plants, but I definitely don’t want to put on compost that’s full of fungus gnat eggs & larvae.

As I mentioned in an early comment, I highly recommend using nematodes rather than DE. They are harmless to the worms (actually, worms end up eating them) and in my experience far more effective for fly problems.

I’ve been using one of those handheld battery-operated tennis racket looking bug zappers and periodically opening up a small part of the zipper top, sticking it inside, and killing all the flies that are stupid enough to stay at the top of the Worm Inn. The problem is I think the flies are actually evolving to be smarter, hah. Most of them immediately start diving down to the lower layers as soon as the electric swatter starts zapping.

I’ve also been cutting back on feeding and watering the worms…trying to kill off the flies before adding more fodder for them to keep multiplying in. I’ve already long since been freezing the food before adding it and until now that was successful.

I moved to a new apartment about 9 months ago and shortly after, I started having these problems with flies. I think they were acquired during the move. A couple of months after we moved, I tried restarting the Worm Inn with all new bedding and food, and even rinsed the worms to make sure no tiny eggs from the flies were stuck on them. Within a week or so, the flies were back again. Maybe some had flown in the bottom of the Inn.

Anyway, I was thinking about trying to restart they system again, but maybe I’ll try this DE method first. One question I have about it, though, is that once it gets mixed in with the overall system, if it dried out too much because we went on vacation and couldn’t water the system regularly, would it then become dangerous for the worms? Now, like Bentley mentioned in another post, although the Worm Inn does dry out easily, it can go for a month or longer without watering if necessary because there will still be a small, wet layer on the very inside that worms can get along in until the next watering. It’s not ideal for their productivity, but it won’t totally wipe out the system. I’m wondering if adding DE to the mix would cause problems in those times when we couldn’t water regularly.

Also, I saw a couple people say “freeze your food”. I freeze everything. I don’t know how I got this infestation.