Looks like Camallanus worms and those are not good for your fish 😨 Dealt with them before and they’re a nightmare
How are they not tubifex? It's hard to tell from this footage, but tubifex would be more like it?
I think they wouldn’t be chilling in the plants unless the plants were decaying since they’re not at all parasitic. Camallanus can be spread through plants or live fish.