Nematodes

[Mentat]

Those are probably white planaria worms that feed on excess nutrients. Pimafix solution (at fish aquarium strength) will kill them; but wiping them out might create a mini cycle and increase the levels of ammonia and nitrites. Good luck !

[Gnag the nameless]

I'm not sure if they're Planaria, they're not sticking to the glass as I've heard Planaria often do. But none of them seem to be coming from Gnag's feces, nor is Gnag acting or eating differently. Is it possible they're just some kind of scavenger that works similar to Springtails? I might do a bit more research on this...

UPDATE:

Well, after doing my bit of research I think they are free-floating nematodes or midge larva. Either way, they are no harm, which is extremely relieving I thought they were parasitic worms or something when I first saw them even so, I'm going to try and get rid of them by doing constant water changes. Did a big one today, it helped.

Thanks,
Caspian