Using super plugs that have been stored

So I have successfully completed my first harvest and I am anxious to move on to my next round.

As I was getting things ready today i pulled out my bag of Super Plugs (root plugs) and some of them are covered in a white powder, almost looks like mildew.

Would it still be ok to use these or should I just buy some new ones on my next supply run. I hate to waste anything

Thanks ahead of time!

I wouldn't. Where did you store them? I keep my extras in the refrigerator. Never been told to do it, just thought it made sense to do so.

Clorox/ bleach soak then let dry in the sun. Make a tea and inoculate them. Should be good to go with beneficial bacteria?

Thanks guys for the info. I like the 2nd idea especially. The owner of my local hydro shop just brewed this tea and ill give it a whirl with some bagseed and see how it does