Suggestions on marking chicks for identification....PLEASE!!

I have 4 breeds, 3 chicks each breed. I want to mark each chick so I can tell who is who. I read all the threads on banding and they were not alot of help. We tried putting a small zip tie around one of the legs last night but we were afraid to put it too tight because we will need room to cut it off after they grow some. (they're 1 week old today). The chick walk around funny for a while (it was very funny LOL) and then shook the zip tie off.
We don't feel comfortable with using the zip ties on them while they are growing so is there any other way to mark them safely. I only need to use three different colors since I can tell the different breeds apart. Can I paint their toes somehow??? Fingernail polish?? Magic marker?? What about food coloring on their backs? Magic marker on back?? It doesn't have to be permanent....just want to know who's who while they are growing.
Please, all suggestions on what is safe and works. Thanks so much.

 

So just use regular fingernail polish?? Anyone on here do it?? How high up on toes?? Do they peck at it?? What about using non-toxic marker on their toes?? Anyone ever do that?? What was the results??

 

Quote:At first I thought "Great Idea".....ran upstairs to sewing room and got all my velcro. Problem.....velcro needs two sides to stick to. Do they sell double sided velcro?? Has anyone used velcro sucessfully??

Also, in a few threads people have said that they use zip ties. Our concern with zip ties is leaving enough room to easily cut them off as they grow. Those of you who use zip ties please tell me how you cut them off as they grow. Even the little zips are kinda tough and we don't want to hurt their little legs getting them off. What tool do you use that is small enough but tough enough.

Thanks