Small black specs on my clone rockwool cubes!

What could these black specs be on my rockwool cubes. Possible the humidity was or is too high, and henceforth i have mold?
They have been under my makeshift humidity dome, i think it is too small i got another much larger one today, took the empty 300 mini candy cane container from work.
The cubes and the clones have been in place since Wednesday, i have been spraying them with Thrive Alive B1 like my sheet for my nuts says so.
Any info is appreciated.

might just be the thrive alive coloring the cubes??

Well it isnt that dark of a liquid but i could be, should i even use the Thrive alive and just use normal ph adjusted water?

i had small shiny black balls and flakes in my rockwool, torned out to be fungus gnat eggs. i noticed the larve crawling around on my seedlings shortly after