Larvae climbing to lid

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Synapze

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Usually when I culture, the larvae climb almost all the way to the top of the 32 oz cup. In my last couple of batches the larvae count is decent, but the larvae climb all the way up to and onto the lids. I'm concerned that airflow through the fabric mesh lid will be blocked by larvae and damage the culture. 

I really have little choice other than try to scrape them off the lid back into the culture. I may also push larvae on side of container about an inch. I can't really think of another option.

Has anyone else encountered this and is there reason for concern? This is a homemade culture using a recipe I found in the forum. I keep my cultures at ranges:

Temperature 75-80

Humidity 60%-70%

They are stored on large trays which have a layer of diatomaceous earth for mite control.

3 cultures are having this issue. 

20180919_093423_zpsglocgo25.jpg


Any ideas or suggestions? 

Thanks!

 
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I can’t say I’ve ever had any larvae climb onto the top of the culture. I don’t keep them in cups, but rather jars, so I can easily reuse them. This culture is 13 days old when I took this picture:

1F1B5D72-812B-48B6-9E80-594C9FBCFE3E_zpsxql54sy6.jpeg


(This is one of my my third generation cultures)

I use a homemade media too, and it works really well. They take about ten days, and then I can see tiny little larvae. 

The jar is a wide mouth quart jar, and I put 1/2 cup of the dry homemade media mix in, and add however much water it needs to look good. For a lid, I use a coffee filter, and they’ve worked really well. They keep in the smell, for the most part, but also allow for some air to go to them. I’m not sure what the humidity is, but it is usually around 70 degrees in my room.

Anyway, back to your original question, I’m not sure why the larvae are going to the top. From what I’ve read, the larvae prefer to stay on something solid, or close to it. Do you, by any chance, stack your cultures? That could be one possibility.

If you happen to have any quart jars laying around, you might try making a culture in one. My jar cultures did better than my 32oz cup cultures, so I have moved to all jars. 

 
From what I’ve read, the larvae prefer to stay on something solid, or close to it. Do you, by any chance, stack your cultures? That could be one possibility.
I don't stack my cultures to prevent older cultures from contaminating the new ones. I used to use excelsior, but started experimenting with plastic mesh (like your example). This particular culture uses plastic screen mesh anchored to the bottom of the container with powerful mini-magnets to prevent fall out. 

I wonder why development is better for you in glass jars. I've always recycled the standard 32 oz containers and sanitize them before reusing. If these suckers don't start pupating, I'll be ordering a culture... which seems a waste of money since so many of them (7 out of 10) arrive like this lovely $17 one. ? It was DOA with no signs of life... it never produced anything except odor and regret. 

20180712_135750_zpsejvzch8k.jpg


 
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Ugh... don’t even get me started on ordering cultures. I ordered one, and it got delayed in shipping, and I was greeted by a huge pile of nasty, smelly, rotting media. There wasn’t a single fly, and there were only a few dried pupae. It’s not that the smell was just bad, that I can take without any issues. It was that the smell wouldn’t go away. I couldn’t out of my nose. It almost made me vow to never deal with flies again, but here I am. And it’s not too bad unless you leave the culture for quite a long amount of time. Plus, the larvae tend to eat a lot of the media, so it doesn’t get moldy or anything. (After the initial mold explosion, until the maggots eat it all) 

I got my initial vial of flies from PetSmart, and I’ve turned it into an ever-growing empire. I’ve got 7 cultures going now, all producing tons of flies. Amazingly, I haven’t had any of them fail. Guess I’m just lucky? 

Anyway, with the 15+ cultures I’ve made so far, I haven’t had any larvae go to the ceiling. You can see it in the picture, the larvae don’t really go above the inward slope of the jar. There’s a few, but they never go all the way to the top for me

 
@ausar318 To be fair, the last culture I ordered was delivered in a box marked multiple times with, "Don't turn upside down or you'll kill us!" Of course, my mail carrier handed it to me upside down. ?

It almost seems many postal carriers read the warning labels and then do the exact opposite, either because they are unskilled or just apathetic. It may have been upside down for the entire trip.

 
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The roach guys sometimes coat the upper part of their enclosures with a thin layer of vaseline, to keep glass climbing roaches from making it up the sides.

 
Hi, the reason larvae climb to the top is CO2 build up. Once they start covering the holes they increase the problem very quickly. 

As for trying to buy flies in the mail, dont get me started...Ive spent more than 300 dollars buying nothing but stinky rotten disgusting slime. 

Good luck

 
@Aristalochia

I agree with your final statement. I luckily was able to avoid wasting that much money on ordering fly cultures on the internet. I was able to find a tiny vial of D hydei at PetSmart and I paid $7 freakin dollars for about 50 flies. But they were all alive, which made it a much safer investment that ordering a culture online, and hoping that it survives the shipping. I’ve got about 7 big cultures going now, so I think I’ve done pretty well for myself. 

A friend of mine, who I met on this forum, offered to give me a handful of Melos, so I figured I’d give them a shot. He didn’t send me a culture, only the flies in a cup with an apple piece. There were a few of them that died, but plenty of them lived so I could start a culture with. I think the key to shipping a culture is to do what my friend did, and then also supply the dry ingredients for the media. From my experience, the media in the culture is just to wet, and it swallows up all the flies when it is turned upside down and shaken during shipping. If I ever decide to sell some cultures, I’ll probably glue an apple slice to the bottom of a small cup, put the flies in that, and then supply a 32oz cup, media mix, and excelsior. It just seems like the best way of doing it. 

 
Hi, the reason larvae climb to the top is CO2 build up. Once they start covering the holes they increase the problem very quickly. 

As for trying to buy flies in the mail, dont get me started...Ive spent more than 300 dollars buying nothing but stinky rotten disgusting slime. 

Good luck
Thanks @Aristalochia! I'm almost certain you're correct. I'll scrape the larvae from the lid and swap out some air and see what happens.  :)

You guys are so cool! ?

 
@Synapze

You might try opening the cuture at least once a day. It would allow for fresh air to be swapped with some of the stale air. It might help...

 
@ausar318 Yeah, PetSmart is way overpriced! I used to buy one of their dumpy cultures every month until I learned how to make my own media!

- MantisGirl13

 
I'm wondering if it could be caused by reusing the fabric mesh lids? When I sanitize the cups to reuse, I do the same with the lids. They come very clean and I let them air dry before using them. Also, I recently needed to quickly increase the humidity in my cultures, so I lightly misted the tops of the lids. Hmm... maybe the reused fabric lids are losing their air flow?? 

@ausar318 I started doing that now. When I had only a couple of cultures it probably wasn't necessary because I opened & fed from them every couple of days.

@MantisGirl13 I rarely read positive reviews for PetSmart. I'll stay up all night catching gnats before I'll buy a culture from them. 

 
I don't stack my cultures to prevent older cultures from contaminating the new ones. I used to use excelsior, but started experimenting with plastic mesh (like your example). This particular culture uses plastic screen mesh anchored to the bottom of the container with powerful mini-magnets to prevent fall out. 

I wonder why development is better for you in glass jars. I've always recycled the standard 32 oz containers and sanitize them before reusing. If these suckers don't start pupating, I'll be ordering a culture... which seems a waste of money since so many of them (7 out of 10) arrive like this lovely $17 one. ? It was DOA with no signs of life... it never produced anything except odor and regret. 

I am curious. Where did you purchase your culture? I order D. hydei periodically from Josh's Frogs, and I have never had a bad experience. In fact, their cultures usually last about a month longer that my homemade version. 

Also, back to the original question, I only see the larvae on the lid when there are so many larvae that they have to go on the lid to find space to pupate. This crawling to the lid could just be happening in my culture due to the large number of flies causing CO2 buildup. Whatever the reason, when the larvae resort to pupating on the lid, I can expect a huge explosion in fly populations in the next week. 

 
Where did you purchase your culture? I order D. hydei periodically from Josh's Frogs, and I have never had a bad experience.
It's a JF culture. Culture quality isn't the issue for me, it's all about how packages are handled during shipment. "This side up!" and "Keep upright or you will kill us!" box labels are practically useless. A good mail carrier will make an attempt to keep a package upright, but mechanical sorting and careless handling leaves package orientation up to chance for the most part. I learned this directly from my local post office after making a couple of complaints. I've had the same issue with healthy cultures I've shipped and now I only ship cultures if a friend has a fly supply emergency. ? This particular culture was delivered in 95° heat with no chill pack and handed to me upside down by my mail carrier, so I don't fault JF for the condition of the culture. They refunded my money without hassle after seeing the photo. That being said, due to the heat exposure, I doubt this culture would have survived regardless of box orientation. 

In fact, their cultures usually last about a month longer that my homemade version. 
Their cultures do produce longer than my assorted recipes, but I generally dispose of cultures after the 30 day mark. 

CO2 buildup was the issue. Now I open all my cultures every couple of days... such a pain. The problem hasn't repeated itself. ☺️

 
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