I suppose the first one in the video is a copepod, but what about the second one (also in the picture) and the little worm-like one? This is a drop of water taken to see an algae, so quite a lot of life there for a random drop.
The first one is definitely a copepod; the second is a Polychaete worm (Bristleworm) of some variety - it's most likely harmless/beneficial. The little, worm-like ones are definitely worms of some kind, but I can't tell what kind from the video; sorry.
Worms like that can be really difficult to ID, so you'd probably need closer up pics of them for a chance at a proper ID.