Silkworm chow drying

[tignish99]

My first batch of silkies started to hatch over the weekend. Yay! Everything is going well so far. I have put the silkworm chow into the Petri dish. I am wondering if there is a time line or a visual way to tell when the chow has dried up and I have to put in more. I want to open up and touch the chow as little as possible so that I do not contaminate the worms.

Any thoughts?

Thank you.