Yeah I also second that - Why bathe a chick? I have never heard of a show for chicks, and there is no need to bathe them. What do you mean by "keeping them clean for reasons" - Chickens should already have the natural ability to keep themselves clean by preening, dustbathing, and not being in unsanitary confinements.
I had to give one of my chickens a bath because she got a case of poopy butt. I gave her a bubble bath using Dawn dish detergent, then blow-dryed her fluff gently on "warm," keeping the blow dryer moving the whole time so I didn't burn her. She loved it!
Just tonite I had one chick with some poop stuck to it, it wasnt pasty butt, more like he sat in some while it was frash and it dried to him.
I just grabbed it with its wings and feet tucked in my hand, and ran it under the faucet with tepid water right on the affected area.
The poop softened, came off, a quick rub of the area and right back into the brooder.
The heat light and dry wood shavings dried him right up, and now hes all good.
No soap, no fancy show chicken, just a cornishx with a shi77y butt.
I shoulda made a how-to video of it for the "pasty butt" crowd, too bad I didnt think of it.