Pest ID needed!

[Dule T&T]

Hi guys
I just dipped some Favia and Blastomussa with unusual tissue recession
After I carefully looked into the dip water I noticed few of these very small critters happily swimming in the dip like it's a bathtub - even after the entire hour in it (I used Red Sea dipX) !
I thought they are small copepods, but before all copepods were killed by the same dip.
Dip didn't affect these creatures at all!!

I tried making a video and zooming as much as I could so you can see them.
They are less than 0.5 mm in size and, as you can see, they are very fast.
Could they be the reason for the tissue recession (in otherwise perfectly healthy system)?
Are they eating my LPS corals?

Any idea what are these?

 

[Spare time]

I am 99% sure that is a copepod of some type. If you'd like to figure things out in regards to the tissue recession, you may want to start a thread on that (or alternatively you can pm me if you don't feel like making a new thread)