Consistency of media

[MantisAnon]

How moist do you like to have your media? I'm starting some cultures, and I don't really want to buy media off the internet, so I've been trying to make some on my own. Most of my cultures right now have media made of sugar, water, and potato flakes, and have a consistency of mashed potatoes. Is this too thick? Should I make some with the consistancy of, say, applesauce? Do hydei and mels require different amounts of moisture?

 

[PeterF]

My media is thicker than mashed potatoes. And it is VERY dry here. I know it seems like it should be runnier, but I don't suggest it.

Also, I use a piece of apple as well. It is to encourage laying, but I suppose it may add some moisture.

I don't use sugar though, so maybe it is a different consistency with the sugar?

 

[PhilinYuma]

Good for you to work on your own FF formula, but your recipe isn't the best. Look at Orin's sticky on the top of the Food and Feeding forum. There is also a huge thread on the subject. There is no reason to add sugar and potato flakes, since both are carbohydrate. I use sugar, but it is to provide food for the yeast whose fermentation stimulates egg laying and provides an excellent food for the grubs. It's a while since I looked at Orin's post since I uses my own mix, but he goes into some detail about water requirements and that will get you off to a good start.

 

[Rick]

You just gotta experiment until you get it right. Not too dry and not too wet. Somewhere in the middle is where you want it. All about how much water you add. The commercially available medium is far superior to homemade so I wouldn't discount it.

 

[GreenOasis]

I have experimented with my media and found this to be the best mix thusfar: 6 Tablespoons potato flakes, 2 tablespoons powdered milk, 1/2 tablespoon sugar, 1/2-1 tablespoon brewers yeast. Use 1/2 cup distilled water, microwave for a minute (till hot or boiling). Mix the dry ingredients in your culturing cup and after pulling the hot water out of the microwave, add the cider vinegar to the water (and food coloring if desired), stir briefly and pour ALL AT ONCE into the culturing cup with the dry ingredients. Immediately stir quickly as it will solidify fast...don't worry if you don't get all the powder mixed in. Replace the lid on the culturing cup while you let the media cool down (so that wild fruit flies won't get in there & lay eggs while your back is turned!) Give it about 15 minutes to cool off, then remove the lid, add a pinch of baking yeast (live, active stuff), add excelsior or folded coffee filters & then add your starter flies.

I have tried several variations of this media and others, and so far this is the one that works the best & produces the fastest. The cider vinegar is not necessary, but may inhibit mold growth and seems to get the little buggers to start laying eggs a lot faster. (I've left it out and it seemed like it took another week or so before they started laying eggs.) You can probably also use white vinegar, some do, but I find the cider stuff works better for me...probably because it has that rotten apple smell.

I have also found that a thick, slightly "dry" mix seems to work better than one that is too soft. When the maggots start hatching out, they "spit" (or something) into the media and make it thinner, so if you make it thin from the get-go, it will be soupy when the maggots start to appear and it will be pouring out on you while you're trying to tap out flies.

If you need a supplier for cheap brewers' yeast, send me a PM...I'm going to be offering it on our website, but I don't have it up there yet!

Good Luck!

-Carey Kurtz-

Green Oasis Reptiles

 

[PeterF]

In my experience the two main factors for production are temp and number of starting flies. The cultures I started with a lot of flies produce ridiculous amounts of next generation flies.

And warmth speeds up growth. Assuming it's not too warm (had that problem).

These are both obvious normal things. But it's worth the mention.

I run enough cultures that I no longer worry about extra warmth, the 75 - 80 in the bugzoo is fine.

But, as a thought, I do keep my house fly cultures on a reptile pad, and that seems to help them. I would worry that it might be too much for the FFs, but worth a thought.

 

[Krissim Klaw]

Its interesting to see all the different choices people use. I use potato flakes, banana, orange juice and some vinegar and brewers yeast for mine. I would suggest starting out dryer because you can always make it moister with ease.

 

[PhilinYuma]

Its interesting to see all the different choices people use. I use potato flakes, banana, orange juice and some vinegar and brewers yeast for mine. I would suggest starting out dryer because you can always make it moister with ease.

Yep. I think that the reason for this wide variety is that the majority of mantis keepers have little or no idea of the nutritional needs of Drosophila sp. No one would try to raise a human infant by going to the store and grabbing whatever baby food seemed interesting, but that is often the approach here. Fruit fly larvae need carbohydrates, protein and fats, the same as most animals, and it is interesting to note few, if any folks on this thread are using active yeast, an important protein source. It seems likely, though that fruit flies carry yeast spores on their tiny bods, which will seed the carbohydrate mix, provided that enough vinegar has not been added to kill them. Remember that the pH of acetic acid is about 2.4, not conducive to the growth of any but the more acidophilic bacteria and fungi, though it is diluted enough, I guess, so that it does little harm or good.

I believe that the success or failure of many of your formulas depends on how good a culture medium for microbes and fungi it turns out to be and how lucky you are in getting a decent growth of air born and fly-vectored fungi and microbes.

Somewhere, I think that I wrote a long discussion on FF nutrition, but since I was not marking posts for easy accessibility then, I have no idea where it is. Still, Google is your friend in this topic, too. Good luck!

Edit: Here's a very old, very good monograph on the subject that you might find interesting:

http://books.google....mberger&f=false

 

[nebrakacinese]

I use Orin's recipe that's pinned in this section, if i happen to make it a little too wet I'll sprinkle a few more potato flakes on it.This way for me the flies don't drown.I did have one culture that became quite runny after producing a large amout of flies.I've read that the maggots vomit in the medium.