Raising houseflies in 32oz pots.

CareyI have set up the House Flies in Pots project, and it has been running for a week, so far with satisfactory results.

Many members have suggested that the "easiest" way is to keep HF maggots of pupae on hand and feed them as necessary. I don't argue the point. The reason that I have gone to the trouble of raising my own is as follows:

1) I want about a hundred flies a day that I can feed live to my mantids.

2) I want a really simple medium that I can set up in a few minutes, is very inexpensive and that doesn't stink.

3) I want to be able to harvest the flies by chilling for a few minutes and serve about fifty pots in half an hour or so, every day, or every other day.

Food: A quart (~1L) of dog food pellets. 2qrts water A few pinches of bakers' yeast.

Preparation: Simmer the dog food and water, stirring occasionally, in a large pot until the pellets soften to make a smooth mixture. You can help the process with a potato masher, the kind that uses a flat metal plate with slots, or a food processor. Spiderpharm Chuck, recommends putting in wood chips, for oxygenation. I did, but shall try without for the next batch to simplify the process.

When it is cool, ladle it into the pots to make a one inch (2.5cm) layer and sprinkle the yeast on top. It should be moist, but not runny. Cover each pot with a mesh, not fabric, lid (see Mantis Place for pix of the two types) which has a hole cut in it inside the inner ring of holes. Block with a sponge stopper. Add about six flies per pot, check over the next two days and add new flies to replace any that die.

Store the leftover food boxes or freezer bags, put it in the freezer, and then clean up! If you don't, the mess will harden in a few hours to something like brown concrete and you will have to soak whatever it's on and scrub it off!

After a week, some of the maggots have started climbing the walls of the pots, getting ready to pupate. In two, they had crawled up to the very top, which is a bad sign, and for the first time, I could smell a faint rotting smell and a hint of ammonia. I stirred the mixture to aerate it and removed the bungs and two hours later, the smell had dissipated and they had climbed down into the medium. Looking good!

To be continued...

why not just the dog food or like chicken?

Flies tend to lay eggs on a moist substrate because the soft skinned maggots need external moisture and though they have very tough rasps in their mouths, I suspect that a dog pellet would be way too togh for them. Also, the yeast needs moisture to get going. Come to think of it, I know that's true, because they have never laid in my open dog food bags.

There is no doubt that suitably rotted, moist chicken (you could add papain meat tenderizer to speed up the process) or liver (used in the infamous "bucket" method") would work fine, but they both stink pretty bad and cost rather more than the dog food mixture.

Actually, I did once culture flies in a whole dead chicken. I had set it out in March, where turkey vultures roost, in the hope of luring them within close camera range. It didn't work, but when I went, all unsupecting, to take the bag containing the chicken to a garbage can, the whole thing fell apart, displaying thousands of bluebottle maggots and giving a stench that rated 11 out of 10 on the disgusting scale! Ain't nature grand?

Sweet idea. I'm going to start doing this.

whats does, "removing the bungs" mean? do you really need that much water to boil 1LB of dog food? your setup seems really nice, is it specificly for house flies only, have you experimented with blue bottles yet? if you want me to ill do it with my BB's

d17oug18 said:

whats does, "removing the bungs" mean? do you really need that much water to boil 1LB of dog food? your setup seems really nice, is it specificly for house flies only, have you experimented with blue bottles yet? if you want me to ill do it with my BB's

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The lid of each wire mesh pot has a hole cut in the center, just like a feeding port in the side of a pot and blocked with the same kind of bung.* You can remove it to add fresh flies, stir the mixture with a dinner knife** to aerate it, smell whether the mixture is getting stinky or not and say encouraging things to the maggots.

I thought the same thing about mixing 2 parts of water by volume to one part of dog food, but that's what it takes.

Ogiga sold me 801 BB maggots (thanks for the shipping notification, mate), so I'll be setting those up next week, but of course, try it for yourself and let us know how it is getting on! The big difference between this animal protein medium and the largely carbohydrate FF medium is that, unless you give it plenty of ventillation (which is why I removed the bungs today; I don't need the flies any more) and stir it occasionally, anearobic bacteria will produce bad smells and worse, ammonia, which will kill the maggots. If things start to get unpleasant in the medium, the maggots will let you know by climbing up to the lid.

* A number of the flies died in the first 24 hours of the first batch. They constantly jostle each other in such a small space, and I think that they died of exhaustion. I shamelessly stole Katt's idea of putting a drop of honey on each bung for 'instant energy" and cut down on losses dramatically.

** I use a "dedicated" knife for this, but if you are using one of mom's knives, be sure to lick it off before returning it to the cutlery drawer! :lol: :lol:

I'm interestedly awaiting further developments and reports...

Another good couple media for raising house flies is Layers pellets (for chickens ) and chick crumbs, obviously both with added water, don't smell to bad either.

Good luck with yours.

GROSS!!!! lol lick it lol oh man thats so gross lol, well i dont know anything about plugs nor do i have any. I also only have clothe lids which i am guessing will get nasty and unusable. ill do what i can though.

d17oug18 said:

GROSS!!!! lol lick it lol oh man thats so gross lol, well i dont know anything about plugs nor do i have any. I also only have clothe lids which i am guessing will get nasty and unusable. ill do what i can though.

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Perhaps you're used to calling the "foam stoppers" or "plugs" instead of "bungs", like Ricks pic in this thread: http://mantidforum.net/forums/index.php?sh...c=14329&hl=

Instead of putting them in the side, though, I cut a hole in the lid. When you get all that aluminum mesh screen, you can soak the cloth off your lids and replace it with a disc of the mesh. In my limited experience, a cloth lid without a bung is likely to kill all your larvae.

It is now 11 days since I started this experiment. The plan was/is to let the whole process from mating to eclosure take place in the pot. This will happen in two of the pots, where the maggots have already started pupating. I seperated out the maggots from one pot yesterday, though, counted them (223) and put them back in the cleaned cup with some moist paper towel crupled in the bottom so that the maggots could easily climb under and over it. By this evening, about 85% had pupated, and I seperated them out. A second pot was beginning to smell a bit -- not nearly as bad as crix in a moist enclosure, but bad enough for me to want to clean the pot out -- and I placed the maggots as before. The wood chips are a nuisance though, since they won't go through a sieve with the dog food mix, and I think that I shall do with out next time. The other two pots scarcely smell of anything, and the maggots are beginning to pupate there, all in the substrate instead of on the sides. It is interesting to note the different times until pupation in the four pots under what would appear to be identical conditions.

Someone mentioned that HFs can be raised in FF medium, so I started a pot of regular FF medium at the same time. It has produced no HFs, but a nice crop of wild FFs

Phil, have you had any success with BB's? Also, how did you use the sieve to separate the maggots? Did you run water over them?

I have some HF pupae coming and I am going to give it a shot. Seems easy enough.

nice findings, i want to try this but i dont know how the heck you are seperating and cleaning without having any escapees or problems. If i can read this post over again and understand it better i will try it out myself. Great job though man, seems to be working out with ease.

Wow, so it is actually working? I might need to start doing this. Paying lots of money and having maggots shipped to me in this hot weather isn't working. The maggots I bought are mostly dead, so the ones I sold to you and Doug probably aren't doing any better (so I contacted the supplier to see if they'll reimburse). Please keep us updated. I probably even have to buy your flies, Phil! ...that's if you decide to sell them.

update: Looks like they're just going to leave it as it is and not be of any help because I didn't choose next-day shipping.

Success! On the thirteenth day since I set up the pots, some of the flies have started to eclose! I have about six hundred pupae from the batch, though the one pot that I kept as I originally promised, without seperating out the maggots, dried enough to destroy the larvae and only yielded about a dozen pupae, which I still had to sieve out from the culture medium.

I have four pots in culture, which will probably not survive my absence starting next week, but on my return, I shall set up for refgular flies, small ones (intermediate between D. hydei and regular HFs for the mantis connoisseur) BBs, and flightless flies if anybody is interested in learning how it is done.

It turns out that it is possible to raise HFs in a FF culure medium, but the few maggots are still not ready to pupate, and I wonder why anyone would bother.

Will house flies pupate in carefresh animal bedding?

what a strange question :huh:

what gives you that idea?

superfreak said:

what a strange question :huh: what gives you that idea?

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It has large granules of material.

Perhaps some one could rig a system in which some of the carefresh rests on some wiring above the fly medium, so that one doesn't have to sort the pre-pupating maggots out of the medium.

Zephyr said:

It has large granules of material.Perhaps some one could rig a system in which some of the carefresh rests on some wiring above the fly medium, so that one doesn't have to sort the pre-pupating maggots out of the medium.

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Yes, that's that absorbent cellulose, "flush it down the toilet" stuff, right? The idea sounds good; house fly maggots (and FF maggots, too, on a much smaller scale) greatly reduce the water content of their hemolymph before pupation, by "flooding." In big setups, you can use a towel for the same purpose.

I was trying to keep the process as simple as possible, though, with a minimum of equipment. I can dump the subtrate in a large sieve and have clean maggots and a few pupae cleaned in less than a minute.

Since my last entry, I have come up with a similar substance to yours, Lizard Litter, which is fine wood shavings, which are absorbent and, being wood, give the maggots something to nibble on before they pupate.

Incidentally, I set up four pots a few days before I left on vacation, and when I got back, each one had produced about 70 full-sized flies without any attention whatsoever.