Forgive my ignorance. But I think these are some kind of pod. Just want to make sure they are a good type and not a pest, that will cause trouble in my tank.
please forgive the video quality it was the best I could do.
It is hard to confirm for sure (understanding it is the best you could do), but it looks like either gammarid amphipods or munnid isopods (or possibly both). I think they are most likely amphipods.