fruit fly cultures

[RecycledAgain]

I definitely considered the Co2 ,, but I assumed the directions were followed . If you added alot of yeast and the ventilation was low,,vince may be on to something.

It could very well smother out the flies..

I never really follow a schedule with adding the bakers yeast,, sometimes I let the empty cultures sit for a day or two and others I immediately add the flies.. (10 - 30 grains for 1/2 cup of media)
I keep coming back to ventilation..

On a side note don't leave the new culture open,, Always cover it as it settles or you will invite unintended guests.

Dan

[beckdg]

vince does make a very logical point. however, i don't know guys... you really think so?

this is where i'm caught in this logic...
yeast... 2 types... check
food for yeast... at least 2 types... check (tators and sugar are both sugar, ie: food for yeast)
but... yeast multiplies like single cells or beneficial bacteria in that each cell splits effectively doubling it's population. healthy yeast produces lots of co2 as it eats/grows.
when mixing yeast/sugar/water to make co2 for injection often times the mixture takes 24-48 hours to start producing co2. not every time but it happens.

osmo-regulation... ph/co2/oxygen/water and the bloodstream. they're all related once they're in the body of an animal... not sure how that effects insects but in other creatures theres definitely something common even though their organs aren't exactly the same.... but they have the same jobs.

too much co2 can lower the ph of the bloodstream while not enough can allow it to raise. this can have the effect of blocking oxygen uptake if the ph is too low but in the first night it doesn't make sense to me that that's what it would be. there should be the lowest possible number of living yeast cells in the mixture that first night... and they may not be producing yet. at any rate... (i may have the water uptake/retention part backwards but you guys should get the idea) low ph [from too much co2] blocks water absorption/retention in critters [including fish and humans] whereas a high ph in the bloodstream can cause us to retain too much.

in any case when the parameters shift too far the drastic swift change can shut down organs or make weird crap happen. in fish/humans it could be anything from bloat/dropsy/water retention to just plain old dehydration. some fish even seem to burst/split at the seams from what i've gathered.

so... if the issue was co2/osmo-regulation related i'd propose the the drastic switch from a co2 abundant (producing) culture to one void of it might have been the issue also.

then there's random incidents. you never know when there might have been a spill in a factory that bags up the ingredients. a few tons of potato flakes could have spilled and the factory workers did their best to clean it up and save what they could and all you'd need is one affected flake placed just right and poured into the culture to cause a disaster... who knows...

feel free to tell me i'm completely crazy here as i'm simply relating what i know and personally don't culture FF's as of yet since i have no need for such small feeders. however i have looked into osmo-regulation/co2/the bloodstream and their relations in conjunction with living animals for other purposes. i've also done diy co2 injection and helped lots of people get started and straighten things out with this information... and i know that yeast cultures normally don't just boom with co2 production in the first night in most cases (although it can happen in random cases). at the same time... the yeast you put in your culture at the beginning should be the minimum the culture has at any point before it starts dying (usually from the ph dropping to low to support yeast growth or running out of sugars/food to support more yeast) and therefore co2 production should increase as time goes on until it hits an apex. which illustrates perfectly that 3 days to a week after the culture is started the co2 production should be significantly greater than that of the first night in any scenario. so basically if they can survive day 3 in the culture than co2 overdose should be of no concern on day one in any culture. on the contrary it might be just as important to make sure co2 is producing so that the flies don't just knock over (pass out) and their organs slowly seize one at a time...

once again... my info was not attained with insects in mind so feel free to let me know i'm crazy as well as how and why.

[RecycledAgain]

I was under the impression that active yeast began making CO2 immediately and the warmer the food source the faster the reaction.

I am reminded of a 3rd grade science project that used a couple of soda bottles and a balloons. The idea was to mix the activated yeast with warm water and the other with cold water and record what happened. (Sugar was added to each bottle)

I still think Vince may be right ..

Was the culture fresh and warm when the yeast and flies went in? I also noticed you refered to one hole for a vent, how big was the vent hole?

Dan

[wolfie2nd]

Sorry I was outta town for a few days. Thanks for all the help and ideas.

[Vince]

Hope the info helps, there's alot of good suggestions from folks but I still think the CO2 was most likely the culprit. I get what you are saying Beckdg and I am certainly no expert, but any recipe I have come across suggests waiting 24-48 hours before introducing flies for just this reason.

FYI... I've tried a few different recipes and found the one on the Understory website to be the most successful here is the link Understory Enterprises Inc. - Culturing Fruit Flies

PS RecycledAgain makes an important point about leaving the culture completely open. Just a couple of regular fruit flies can wreck your wingless culture.

[beckdg]

active yeast (theoretically) does produce immediately. dead yeast, inactive yeast, etc. doesn't though. dead packets are not uncommon.

yes, temperature is a big factor. my house stays at 68*F, tops so my mixes peak at best at what i can create at the beginning of a mix since i can kick start them 30*+ higher.

too much or not enough... there's something to look into if you'd like... osmotic shock, osmo-regulation. either way it's what's being suggested mostly.

i believe it's somewhere around 110*F that common yeast just dies, so be careful with "warm". sometimes people don't get that "warm" means just a couple degrees over feeling it (think of testing a baby bottle for example).

i think there's a good chance it could've been a co2 overdose also. sudden bursts at the beginning of a mixture does happen. remember, though... when injecting co2 into a planted fish tank, folks do things like count bubbles to quantify what they're getting. i know how sketchy/inconsistent it can be from a yeast and sugar mix.

lots of good info here, definitely.

[JimO]

I agree with the CO2 theory. If you put the yeast in while it is warm and wet, the yeast will reproduce rapidly producing both CO2 and alcohol. If you have ever baked bread, you can imagine how much gas can be produced in a short time. These gases are what make the bread rise. Anyway, CO2 is heavier than air, so it will displace the air from the bottom up. It's possible that the entire air space in the container was displaced.

I usually let the media cool and solidify before I sprinkle yeast over the surface and I've never had a mass die-off.

Give it another try and only add a few flies at first. If everything is ok after about 12 hrs, you can add some more.