i have had isopods for around four months now, and have had my current enclosure for 2-3 months. they recently started breeding, and i saw a bunch of the little babies. I went on a trip for around ten days, and left the isopods in the care of a friend while i was away. (to make sure it was damp enough, feed them once or twice) they did a pretty good job, they all seemed to be doing fine. but i noticed there were less of the babies than when i had left, and around a day or two later i opened the lid, and there was fruit flies. i heard that these can be a big problem for isopod enclosures as the flies can breed and such, and was wondering how to get rid of them? I couldn't find any videos or solutions that would work, and i don't want to have to start over again. here's a picture of the tank from before i left. not much has changed, other than there's a few flies now.

Hello! Thank you, actually. I have been feeding and watering them less lately (even though I didn’t see your reply) and it seems to have worked, as I don’t see any gnats anymore- I’m glad I know what they’re actually called though, and I will do more if the problem returns :)
(edit: my isopods seem to be happier too, and they’re growing in number again)
Hmm… are you sure they are fruit flies? Check the substrate for small larvae. They will be white with small black dots for heads. I assume they are fungus gnats, not fruit flies, and they are a result of mold overgrowth, damp substrate and warm temperatures. It is common to have them if you have house plants that you are overwatering or to get them from substrate from someone that has them as well. They’re relatively harmless, but they do compete for food and breed phenomenally. You can deal with them by removing all of your isopods into a new bin with heat treated substrate and either heat treating the substrate you are currently using or just toss it. I would toss it, but make sure to seal it in a ziploc bag. You can prevent the gnats by making sure you don’t overwet your substrate in the future and try not to over feed, causing more mold growth than your ispods can consume. Also, extra high humidity may be what caused your culture to slow its growth as well, they may just not have been that happy!! I hope this helps!! I know I’m a few months behind the ball!!