Mold In Larvae Container

Ratmosphere

Ratmosphere

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This is my second time changing substrate for my larvae. I used more wood this time and am waiting on an order for proper substrate to come in, so hopefully I can give them better nutrition. However, there is poor ventilation inside these containers and I see white spores of mold growing on some of the decaying wood chips placed inside. Is this an area of concern for them? Also, how many times should I keep the substrate wet? It seems like sometimes the substrate is sprayed too much.

 
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It's usually better to have minimal ventilation in containers with larvae as it prevents the need to monitor the soil moisture and the frequent disturbance of having to spray or mix the substrate to give the substrate a proper and even amount of moisture throughout it. You should only need high ventilation if you live in an area with humidity with near or at saturation or if you notice the substrate breaking down to the point where it's liquifying due to excessive moisture. If you've set up the substrate properly at the start, you should not need to ever spray the substrate to maintain the moisture level if you haven't provided excessive ventilation.

Are you seeing spores or mycelium? Mycelium is normal and sometimes beneficial to have as it continues to break down wood to the point where it's useable for some types of larvae. If it's actually spores, you have some sort of mold that may be harmful as some types of mold are very aggressive and are known to be able to get into insects as spores and kill them as they use the larvae as sustenance. Mold growth usually means there's an excess of nutrients free in the substrate and you may need to put it in a bin to let it break down and allow microorganisms to use up the excess. You can also take steps to sterilize the substrate you use to ensure you don't introduce harmful microorganisms.

 
Yeah now I'm seeing green mold or something today.
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Green mold is pretty normal in small amounts and tends not to be an issue.

If you think the substrate is too wet, I suggest digging down in the bin and taking out a handful of substrate from the bottom and squeezing it in your hand. If a few drops of water come out, the substrate is at a good moisture level. If the substrate is mushy, almost liquid, and a large amount of water comes out when you squeeze it, your substrate is oversaturated and you will need to do something to remove the excess moisture.

 
When I see mold, I usually just open the lid on the container for a couple of days and let the top layer of substrate dry out. Then, I remove the top layer and put the lid back on. That usually seems to stop the mold from taking over.

Cheers

 
Thank you guys. Right now the soil is moist but not enough to squeeze out water. Do you reccomend I add more water?

 
Alright guys, good news. The mold is now gone because I replaced it with some new substrate. So far I see no mold. However I ran into something I never ran into before in the past 2 months. This would be a small fungus gnat inside the container that I saw and then squished. I do not understand how these can come through a hole this small inside of my container. Beside heat treatment, is there any alternatives to keeping these fungus gnats away?

 
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Gnats are completely harmless, so the best way to get rid of them is to prevent them from getting in the tank.

Orin recommended to use pinholes for ventilation because thumbtack holes are large enough for them to get in.

 
Fungus gnats means at least some part of the substrate is too moist - the gnat larvae like wet substrate. Sometimes it's all of the substrate - sometimes condensation rolling down the sides can make the edges at the surface wet enough. Take the lid off and let the substrate dry out a bit.

 
UPDATE:
Is it normal for a larva not move a lot? I thought an L3 Lucanus Elaphus would be hungry frequently and moving around quite often. However, he just made a tunnel that you can see through the container and he is just dormant there for the past few days.

 
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UPDATE:
The one larvae that made its tunnel is moving around again. However, my other L3 Lucanus Elaphus in the other container is always seen coming to the surface wiggling around. This has me concerned to the max. Even when I bury the guy he comes back up and just rolls around. This is also the container where the only fungus gnats are found. I know when the larvae come to the surface something might be wrong with the substrate or room temperature (set at 69°F.) I put about 20 breathing holes in the top. When it comes to the surface it still feeds on the substrate sometimes. However, the other L3 of the same species and my other larvae on the same substrate are doing just fine. Any ideas ? I don't want it to die.

 
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If you have them in different containers, you have to remember that the substrate will not all be the same once it's divided up. Each container will eventually vary in substrate moisture and the variation in moisture will change things up a bit.
Check to see if the moisture is even in the container and whether or not it's different from the other containers. It's very unlikely that it's coming to the surface due to low levels of oxygen as beetle larvae tend to be very capable of dealing with decreased oxygen levels and the fungus gnats suggest that something about that substrate is different from the substrate in the other containers. If you can't figure out what's wrong, you should change the substrate and see if there's a change in behavior.

 
UPDATE:
Just checked one of the containers and found some mycelium growing. However, there is no green mold. I removed the mycelium and placed it into a small salad dressing container with some of the same wood flakes on top. I am going to try some experiments with it.

In other news, I have to heat treat the substrate soon. This is due to so many fungus gnats. I was considering making vinegar traps and putting it near the containers as a temporary solution but fear I will bring mites. Any suggestions?

(Photos deleted.)

 
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New keepers get a little worked up about fungus gnats and mold. Outside my house right now I can't take four steps w/o seeing four species of fungus gnats all over the place and they are pretty much impossible to completely keep away if you have more than a few containers with dirt in them. The tiniest gap in a lid and even pinholes sometimes don't keep them away. I swear they sometimes drop eggs through my lids with pinholes in them, laughing diabolical little laughs all the way. Other times I know they're just waiting in hidden perches for me to open a container and turn my head so that they can dive bomb the container while I'm not looking.

Anyway, I don't personally get worked up about mold or fungus gnats. It's really comforting to see a similar general response in this thread but the original poster should (and I almost hesitate to suggest this) post new threads as the topic/questions change. This topic is titled "mold in larvae container" and some care should be taken to keep that the only topic of conversation in this thread. I used to have some help moderating the forum. I miss those days.

 
UPDATE:

Today I found mites in the containers. What a nightmare. Changing the substrate right now as we speak as well as heat treating. Hopefully we will get rid of these annoying gnats as well!

Im only getting worked up because in the summer I know it will be worse. I feel that even in the adult habitats in my room will get them. I have the larvae in my basement and the imago inside my room.

However I fail to believe there isn't a way to regulate them. I know somebody on this forum that I just saw used sticky tape to catch fungus gnats. I might try that method.

 
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