Look like fungus gnat larvae. How late are u in flowering? Fortunately fungus gnats don't cause too much harm, they only lay eggs which then turns into a larva, these little fucks do feed on roots but can only thrive within the top 2"s of medium. So if ur late in flower, the damage they do might be limited. They just get really annoying as their population increases, flying in ur mouth and shit...
If u choose to rid them, use a top layer of sand or diatomacious earth. Or if u choose to use a product of some sort, use one derived from essential oils like sns 203, neem, etc.
I stay all natural when it comes to prevention. Aact + ogbiowar, and neem oils
Edit to add: could be springtails too