Preventative measures failed

[Ratmosphere]

Earlier in the year, I heat treated and stored a huge amount of substrate for rhinoceros beetle larvae. The substrate was stored in my garage where it is extremely cold. I took it out today to fill up containers for larvae that I just found. When I brought it inside, I immediately noticed fungus gnats running through the container. When I mixed the substrate I found a good amount of fungus gnat larvae. No matter what I do I cannot prevent them. I hate them so much!

[Titanus]

I seem to always get them when I use natural substrate. Now that I'm using flake soil, they seem to be at minimal levels. Having said that, they don't really bother me, and they pose no threat to the larvae.

[charx53]

Was the substrate stored wet or dry?

[charx53]

Do they pose a threat to the larvae? And how do you get rid of them if I notice some?

[Ratmosphere]

No threat to the larvae. I would just have to heat treat it again and I'd probably be fine for a while. The fungus gnat larvae are only under the first layer so it's not too bad.

[Titanus]

Heat/freeze treating will obviously kill any fly larvae that are present in the substrate, but it will also kill beneficial bacteria and fungi that are actively breaking down lignin. There's actually a huge amount of debate as to whether or not "sterilizing" substrate is beneficial, pointless, or potentially harmful. Take a look at any of the big time breeders in Europe and you'd be hard pressed to find a single one that sterilizes their materials.

 

You've got to understand that the substrate we use in breeding beetles is in and of itself, a living organism. It's full of a multitude of bacteria, fungi and (generally harmless) mold. All of these things add to the substrate and continue breaking it down. As for the flies themselves, they don't harm anything and are a minor nuisance at worst. If you've got them, you'll never be completely rid of them. Populations wax and wane with seasonal fluctuations, I always seem to have more in the winter.

 

Either way, small Dipterans are just a part of the hobby, and in my personal opinion, attempting to sterilize every last bit of substrate is asinine and more of a headache than an actual help.

[charx53]

Heat/freeze treating will obviously kill any fly larvae that are present in the substrate, but it will also kill beneficial bacteria and fungi that are actively breaking down lignin. There's actually a huge amount of debate as to whether or not "sterilizing" substrate is beneficial, pointless, or potentially harmful. Take a look at any of the big time breeders in Europe and you'd be hard pressed to find a single one that sterilizes their materials.

 

You've got to understand that the substrate we use in breeding beetles is in and of itself, a living organism. It's full of a multitude of bacteria, fungi and (generally harmless) mold. All of these things add to the substrate and continue breaking it down. As for the flies themselves, they don't harm anything and are a minor nuisance at worst. If you've got them, you'll never be completely rid of them. Populations wax and wane with seasonal fluctuations, I always seem to have more in the winter.

 

Either way, small Dipterans are just a part of the hobby, and in my personal opinion, attempting to sterilize every last bit of substrate is asinine and more of a headache than an actual help.

Kind of like the same thing with a small amount of mites on beetle larvae as well, yeah? So if I gather rotted wood for my larvae and beetle breeding.. should I sterilize it or not? I sterilized the logs for my D. Tityus to climb on. I've gathered a good amount of rotted wood just recently. I want to dry it out (as it it soaked from the rain, I had it outside) and then store the materials dry if I don't use it right away.. Now.. should I sterilize it or not? I have been trying to figure out a better way to do so anyways.. If I dried it out and chopped it all up and kinda sifted through and beat most of it.. would it likely kill anything that may harm the larvae? Therefore..not needing to heat treat? Very difficult to figure out which way is the right way to go...but I suppose it is all trial and error.. Any thoughts?

[Ratmosphere]

You could boil it or use other methods of heat treating; it will definitely kill the mites. I always heat treat my substrate so I can prevent mites.

[Titanus]

I wouldn't bother heat treating it. If you're going to be drying it out naturally, that'd be enough to kill off most any pests. Things like fungus gnats and mites are very sensitive to desiccation, and controlling moisture levels is a great way to get rid of them.

 

The biggest contributing factor to having mite/fly explosions is excessive nutrients and humidity. Adding protein supplements can cause massive outbreaks. Now, don't get me wrong, I add the occasional lump of moist and meaty, but I make sure the substrate is a -little- on the dry side both before and after feedings.

[Ratmosphere]

@titanus, Are you against heat treating because it kills some beneficial gut microbes? How much of the substrate do you dry out? I never used this method. I always keep mine moist but not enough to squeeze water out of it.

[charx53]

I wouldn't bother heat treating it. If you're going to be drying it out naturally, that'd be enough to kill off most any pests. Things like fungus gnats and mites are very sensitive to desiccation, and controlling moisture levels is a great way to get rid of them.

 

The biggest contributing factor to having mite/fly explosions is excessive nutrients and humidity. Adding protein supplements can cause massive outbreaks. Now, don't get me wrong, I add the occasional lump of moist and meaty, but I make sure the substrate is a -little- on the dry side both before and after feedings.

I think I may try this method. Thanks for the advice!

[Ratmosphere]

@titanus, How much do you dry the substrate out while still managing to keep the larvae healthy? I'm curious because I would like to try this method.

[GladysMeyer]

Is this method effective?