Identifying chicks

[klf73]

I wanted to get hatching eggs from two different people. What I wanted to do was keep track of which chicks came from which person. I thought about nail polish, but wasn't sure if the non-nail polish ones would peck at the polish. I was looking for something to put on newly hatched chicks so I don't think the bands will work. Any suggestions?
Krista

 

[Guitartists]

I used a non-toxic marker and marked their heads. I didn't have any trouble with picking or anything. And when it started to wear off.... I re-marked