IMO, those ties are too big for chicks.
With my chicks I start out with the thin 4" ones. Once they get to about a pound I can switch them to the 8" ones.
These look like the heavy duty ones I have, which are quite heavy. I've used these before, but only on adults.
With my chicks I start...
This is what I use (those are 4" & 8" tie-wraps):
I too have left them on too long, :oops:, and this pair of cutter works very well to get them of without doing more damaged to the leg.