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I've been doing this for five years and I still can't get it right. I'll make 3 or 4 cultures and add flies and everything thing seems to be going right - I can see maggots forming and they start climbing the sides and going into a pupae and then hatch and then nothing. Sometimes the cultures are good but suddenly they stop producing.

I normally leave the cultures exposed but in the house. I've heard humidity is really important and some people keep them in plastic containers.

I use Josh's Frogs fly media and it's good. I can produce booming cultures. Sometimes I have so many flies I have to empty some of the flies outside. I normally have a problem during the summer but just this week I ran into problems again.

Any ideas what I'm doing wrong?
Check to see what the humidity levels are in the room that you're keeping them in. IMO it should be at least 50%. Between 50% and 60% is ideal.

10 bux they're drying out. A dry culture is a dead culture.
When you say dry, what do you mean? Every once in a while one of the cultures will get a crust on it but it doesn't effect it from being a high producing culture.

I'm going to set-up a Sterilite tub with a false bottom so I can have water at the bottom so it can help create humidity. I've seen someone else do this.

I just caught in a bad place. I knew I was going to have problems so last Saturday I ordered fruit flies. They still haven't got here. This company I use has good flies but they refuse to use FedEx or UPS. This company is in San Diego and I'm about 500 miles north of them. I've always had this problem with them. I doubt those flies will be able to survive five days in a box because I ordered bulk flies. I have three new cultures going right now that have pupae on the sides of the cup but it will be at least two days before they hatch. It's going to be close.

I've been considering getting out of the hobby just for this problem. Raising the flies isn't the problem but buying flies and getting them to me within two days seems to be impossible.

I've got three cultures that are producing right. O
By dry, I mean the media and pupae drying out.

If you put a glass of water in a room with 20% humidity it won't last long. Take the same glass of water and put it in a room with 60% humidity and it will last 3 times as long. The moisture in your media could be getting the life sucked out of it if the humidity levels in your home are low.

An escaped fly will always be searching for a source of moisture. If they don't find one they die quite quickly.

The crust you mentioned is a sign that the media is too dry (or mold) Try adding a bit more water to it and put them in a room with a humidifier, if you can. Set it at 55%.

Flies can also pupate but never hatch, if a culture is to dry.

Another gauge if the media is to dry, is that the pupa will stay close to the bottom when emerging. In a "healthy" culture they'll pupate 3/4's the way up the sides, if not more. In a wet culture you'll see them on the lid, meaning it's on the wet side.

ETA: Most times flies don't survive shipping, but the larvae usually do.
The best way to counteract the winter dryness is to simply add more water to the media when you make your cultures.

Storing the cultures in a humid 'box' is not as good. Mold and decreased production happens that way.
Phil,

Personally, I think the best way to culture is to keep making the cultures consistently and control the temps and humidity in a small room.

Think "laboratory" control, control, control, gives you more consistent results.

Adding more water to a culture when your home is 30% RH is a gamble IMO. There's no real "control" when doing that. We can get wild swings in humidity here, especially in the spring and fall. One day it can be 40% and the next 90%. I ALWAYS here about culture crashes at these times of year.

Making the cultures identical and controlling the environment will always bring better results.
I should have said the easiest way. I agree with your principal Glenn but I doubt more than 5% of US hobbyists have any kind of room they can devote to frogging.
Philsuma Wrote:I should have said the easiest way. I agree with your principal Glenn but I doubt more than 5% of US hobbyists have any kind of room they can devote to frogging.

I agree and I use the entire room for flies, but have a large collection.

But, if someone has an office, den, sewing room, wherever you keep your flies, why not toss in a humidifier heater/AC and shut the door when not using it?

It's the simplest way to get consistent results.
I've actually have had cultures where the pupae were all the way to the top and even in the crack of the lid. I forgot that in the winter the air dries out.

There have been times that I made the cultures with too much water and although they were fine in the beginning once the maggots started growing and started pupating the culture material started liquefying.

Anyway - I finally was able to get my flies and make new cultures and still have flies left over to feed. From here on out I'm going to keep track of everything I do when making cultures. Where I live in California the winters don't get extreme. Every once in awhile it will get down 24F at night but that's it. You guys brought up so etching that I forgot - and that's the air dries out during the winter months. In the summer months I have the opposite problem and the temperatures get too hot. I think I read that after 85 degrees the flies quit breeding.

I think tomorrow I'll go buy an inexpensive humidifier and stick it in a back bedroom along with the fly cultures.
Are you using the standard plastic cups and fabricote lids? Do you have ventilation in the individual cups. Maggots will 'climb' to pupate when there is less oxygen available.

I have dealt with huge and varied production due to season changes and mixing and making my own media. There has NEVER been a consistency or other media issue that I did not surmount over time and effort.

Just keep at it. Maybe your master fly selection needs to come from another source.
Standard 32 oz cup with fabricate lid. Is it possible I could be using to much bakers and brewers yeast?

Anyway, I'll keep trying to get it right. I've tried other sources for new flies but they come in loaded with mites or they're flying. Let me know if you have a good source.

Thanks,
Frogopolis Wrote:Standard 32 oz cup with fabricate lid. Is it possible I could be using to much bakers and brewers yeast?

It's possible. What recipe are you using?

Frogopolis Wrote:Anyway, I'll keep trying to get it right. I've tried other sources for new flies but they come in loaded with mites or they're flying. Let me know if you have a good source.

That ain't good...Starting out on an up hill battle sucks. Finding a local hobbyist is probably your best bet. I'm sure Phil can help with that.