What looks like might be mold on top of rooter cube? very fine...

I'd post pictures but I don't think it will come out. In my clone dome area I've a few clones attempting to root and on the top of the cubes a thin speckling of white-ish is there. The cubes came with mycorrhizae in them...so that may be it

OR IS IT SOMETHING WORSE?

I use mycorhizae all the time its one of my best kept tricks but I use it in soil and I have never seen anything white on top of the soil bro so I doubt it the mycorhizae

Is the cube dry where the white is??? just sounds like some leftover salts from your water

i have white mold on top of my rooting cubes sometimes when the cube stays wet and there's light hitting it. scrubbing it off, covering it or burying it in the soil when i transplant fixes that. it looks like little white balls. and if you try and pop them you can see the spores fly.

if it's furry like really thin cotton then that's fungus i believe. can be badd shit.

but if it looks like truepunks when it's dry then it's definitely leftover dried salt and is not a problem.

thanks guys! sounds great. I've never had this happen before but I usually use a different brand of cubes.
After this I don't think I'll use them ever again