I agree that red lights are much better and may solve your problem (if you are not already using them), but it could just be that you have a very aggressive chick (since you have 23 chicks that are not feather picking). If you had more chicks with this problem, I'd be more inclined to think there was an environmental or feed issue.
My chicks were raised with red heat lamps from the beginning, plenty of space, correct temps, even monitored free-range time in the grass, but I still had 1 RIR chick that would not leave the others alone - it was very cannabilistic. Once I returned it to the feedstore, the remaining group of chicks did very well - no pecking or picking problems whatsoever. Hopefully your chick will learn better manners after its time-out.
My chicks were raised with red heat lamps from the beginning, plenty of space, correct temps, even monitored free-range time in the grass, but I still had 1 RIR chick that would not leave the others alone - it was very cannabilistic. Once I returned it to the feedstore, the remaining group of chicks did very well - no pecking or picking problems whatsoever. Hopefully your chick will learn better manners after its time-out.