Does anyone know what this is?

These keep flying around my grow tent clones aren’t growing like they should lower leaves are yellowing and dying.

Vinegar flies, or Chymomyza Amoena

Pretty much a fruit fly

Thank you. Are they feeding on my plants?

Just get more airflow at pot or dirt level they hangout on top of the soil.
Or hang sticky traps.

That was the fucker on pence hair ....

In the uk they they called house flies

What's the damage you're seeing? Ive had some unidentified damage recently, and sticky traps found me these guys in my tent too. Probably migrated from my worm bin.
Haven't been able to find anything definitive yet on harm they cause.