moscerini

Stop feeding from the top.. and as i see on the pictures the soil in every picture fully wet. Let the plant have some dry time. to much moist gives the gnats a perfect bed to lay down eggs. Let the soil dry for a week. And start feeding from the bottom. Let the top of the soil stay dried. U will never have gnat issues

I have a diary up on dealing with them. It has many methods, depending what you have on hand. Also I've learnt other stuff to get rid. But basically. You need to implement to methods. 1 for the fliers 1 for the eggs that have been laid. You need to do these things both in conjunction with each other. So, yellow sticky traps, fruit fly traps. Hang them near your lights on string at dif levels. Then, you need to sort the larva out. So you'll need to let the soil dry out. And any larva that have turned into gnats in your pot that are waiting on their wings. So. Bury traps and push soil up around the edges so they've to crawl over it. And if you put some cinnamon in thy middle its a natural fungi that they'll go to and hence get trapped. You can feed water from the bottom up for a few days. (This might cause issues of its own depending how long you have to do it that way) And soil dried out. Scrape a few CM off the top. So any inert larva won't hatch once you wet soil again. Have a look at my diary. I go into how you can use ethanol/water mixes to kill larva or you can use H202/water but i take it u on the organic route..hence the flies. Mainly they come in your bags of soil. And then when you water the larva already in the soil goes active. If you need any help more on this feel free to DM me In future. Treat your soil by way of putting in oven at 220c for 30mins. Will leave a smell for a bit though. So I prefer treating my all mix/light mix soil by boiling water pouring through the pot. If you have a hot enough shower you can just use that. It'll kill any larva. You'll have soaked soil.. so when potting, place some treated soil that you've separated and dried out.. then placing your seedling in the dry soil it'll give it time to grow and by the time it gets to the wet, that should be at a stage where it'll be a lot drier. (Or you can just let the soil dry out. But that'll take days. Feel free to DM me. There's a lot more on my diary, gnats, fruit flies. Good luck.

How about a Drosera or three? growdiaries.com/diaries/164285-grow-journal-by-z4z0z

Beneficial Nematodes from Amazon, if you order today they should be there in 3 days if you have prime....

Bti will control it within 2-3 weeks.. using sticky traps to kikll some adults will help speed that up. "dunks" are for a reservoir and "bits" are for top dressing -- usually 1 top-dress per 3 weeks is enough. The dunks you leave in the reservoir and they slowly dissolve releasing more bacteria. Depending on current, might last 1 month or so, but often dissolve faster in a res with current / bubbles / agitation etc. In future, you can use these pre-emptively and avoid the problem altogether. This is safe for young plants too. pop a couple bits into a solo cup or whatever. it'll be 99% effective.. you my still see 1, maybe 2 gnats flying aound... it kills larvae, so it'll take 2-3 weeks to fully go into effect. won't do anything to later stages of gnats. Any soil stored outside is likely to come with gnats. unless you know the substrate has been properly stored, always adding bti at start is a good idea.

I had a huge issue with gnats and using Bti and second what gREEn7o0 suggests. Using a solution of Bacillus Thuringiensis subspecies Israelensis (Bti) (aka Mosquito Dunks) mixed in with every normal feeding will kill off the larvae. Most of the root destruction is done by the larvae and not the adults. During veg, spray a solution of cold pressed neem oil (always mix with soap and water first) on top of the soil after watering to keep them away from the soil. Avoid using neem during flowering. You can also manage the remaining adults using dry diatomaceous earth sprinkled on top of the soil after the soil dries up a bit. Do not wet DM ahead of time. Pest detection. Continue using yellow stick traps for pest detection. These are essential in monitoring your progress on killing off the larvae.

Unionize them they are hard workers. GnatPower!

Yellow sticky traps, cover soil with perlite, let soil dry out, Bacillus thuringiensis.