7week old silkie chickss not eating

[Lizjh]

My silkie chicks seemed a bit quiet this morning and then I noticed their food bowl was still full. I took it away for an hour and when I put it back they paid no attention to it. They are incubator hatched and in an outdoor brooder, without heat. They do seem thirsty. No blood in their bedding, but I have put a cocci treatment in their water. They are quiet, all sitting down instead of running around like they usually do. Very concerned about them. Any suggestions/ideas please?

 

[nuthatched]

Are they eating the bedding? What's their food?

 

[Lizjh]

Thanks for your reply!
I have them on chick grower with added Amprolium for cocci(added by manufacturer, not myself).Their bedding is Horsemate, pellets you add water to, and it breaks down to look like sand. I have always used it because it stays dry and is easy to clean.
As to them eating it, I did notice them pecking around on the floor , maybe they are?! If so, how do I prevent that?