Thanks everyone! I do have a small bowl of chick grit out for them, which they use as needed. I feed them starter, both dry and fermented, plus fresh leafy greens and yogurt. They're absolutely nuts over any kind of greens!
Yesterday we took them out on the lawn in a pen and let them run around in the sun for a couple of hours while we worked on the coop. They loved it! Later, after I put them back, I went to check on them and all 16 chicks were piled up in the tub (brooder) completely passed out. It was so cute - you could almost hear them snoring and see the drool, lol. They didn't even wake up when I went in to see them - just like toddlers who zonk out after too much excitement. Later they seemed invigorated - their games of keep away were more spirited than usual. I think they were inspired by the great outdoors!
I'm really enjoying their personalities - the leghorns are so curious and braver than the others, but detest being held. They jump and squawk like they're being killed every time I pick them up, lol. The BLRW are sweet and calm and like to snuggle. The first Barred Rock is the same - sweet and cuddly. The other 2 (from a different store) are spastic and don't like to be held. The SLW aren't really standing out to me at all, personality wise. They pretty much just blend in with the others. The EE's (Ameracaunas) are also very sweet, and the bigger one is always making eye contact, with her little head tilted, like she's trying to tell you something. She's an observer - always a little away from the others, watching, taking it all in. She has very intelligent eyes and demeanor and enjoys being held. The salmon fav's are not growing as fast as the others and are middle of the road as far as friendliness - once you pick them up they're pretty calm and sweet. The Brahmas are a lot like the leghorns but I love how big and robust they are!
I'm really enjoying them!