White fuzzy mycelium or mold on cakes?

A first-timer friend has a question:

The completely colonized jars were opened, top vermiculite was scraped off, cakes were loosened by tapping, then water was added and left to soak for five hours to rehydrate cakes and get them ready to fruit. Then, they were put into a tupperware container with perlite on the bottom (on their jar lids). An air pump is set to inject air for 1/2 hour twice a day.

Four days later, all four are white, but two are now fuzzy. Is it mold, or could it just be the mushroom mycelium outgrowing its cake?

 

the fuzziness is good as long as its white.

 

it could possibly be mold too. mycelium isn't the only white culture. you will find out when they do or do not fruit.

 

I've seen a really white fuzzy mold grow on wood...
Could it be the feared spiderweb mold?

 

pictures would help a whole lot

 

cobweb maybe???

 

Apparently, it's all white, and cobweb is supposed to be a little grey.

From what I've been reading, I believe this should be normal healthy mycelium.

Whew...