Fungus gnats from soil

Hey!
One day ago fungus gnats started coming out of my soil! I tried fighting them back with some coffee that I spreat around my plant and sticked matches into the soil, here a picture

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I was wondering if this will have an impact on my pH level and if yes what I can do to get it back to normal?
Is there a better (maybe not too expensive) way to fight those gnats? If so please tell me!
Greetings, Deibiddo :slight_smile:

cut up some potatoes and place them on the soil in a few days the potatoes will be covered with the eggs and gnats. works awesome !

Will

And what about the coffee and the matches that I already used? Should I just take them away? Thanks!

All ya need is the potatoes

Yes remove,them, matches contain sulfur which plants do like but coffee on the other hand is very acidic watch your ph

Good point my friend.

Will

Should the potatoes cover all the soil? Or just spread them out?

Spread them out