Coco fiber fly issue

[Bonesz203]

Couldn't find an appropriate place to post this so if there is a correct location please move if necessary. Anyway I was just wondering if anyone else has ever had this issue before. I have a gargoyle gecko on cox fiber and it stays moist most of the time and no matter what I do I can't prevent some type of fly from breeding. My dart frogs and my crested gecko are also having this issue and I need to scrap it fast so if anyone has any ideas please let me know. Sorry this isn't about a dragon but I figured I'd ask

 

[Taterbug]

Are they maybe fungus gnats? I have these due to one of my snake setups.

I think I have read about people dealing with them with using nematodes and predatory mites in animal enclosures with live soil substrates. The dart frogs I imagine could just eat the flies but you may need to considered alternative substrates to the coco husk. Unfortunately since you can't use chemicals you need to eliminate the breeding conditions for the flies and even still they might come back.