The chicks took the transition to the Grandpas Feeders in their stride.
For the first few days, they were wedged open. The chicks had no hesitation in eating from them - and, being chicks, in them - so we dispensed with the small feeder.
Some time ago we moved the setting so that the feeders were partially wedged open. Because we were having to shut the feeders at night, we couldn't face using the supplied screws, instead DH fashioned a rod to use which could easily be pushed in and pulled out.
This partially-open setting is the bit which freaks out established hens but, we discovered to our joy, not the chicks. Of course the clanking made them jump. Of course they got off immediately. But they are chicks, and they eat a lot. So, it didn't take them long to get over their fear. Within a day, they were ignoring the clanking.
We watched carefully. Some of the chicks got on to the treadle and it hardly moved. Others got on, and it dropped immediately.
A couple of days ago, we introduced growers pellets to the chick crumb, and this was an immediate hit. In fact, we found they ate the pellets in preference, so we're topping up with just pellets now but making sure there is a little crumb there for any chicks that might prefer it.
This morning DH let the chicks out. When I came downstairs, I noticed that he'd shut one of the feeders completely, leaving the other one wedged partially open. I was surprised, as I'd found it most effective to do the same to both feeders. I asked him about it while we were having breakfast, and he said that was how he'd found it, the chicks were using it, so he'd left it. Fair enough.
A bit later on, I saw that he was right and that chicks were happily using it. I decided to shut the other one as well. I topped it up first with some pellets, then shut it, and then I came back inside to get another scoop of pellets for the other feeder. When I opened the already-closed feeder, I could see that there was a chick inside the hopper. Despite the heat of the day, I went very cold.
Gingerley, I opened the lid of the hopper, and there was one of the rogue chicks. It looked at me, witha a "What? What have I done?" sort of look, hopped out, and then went off to the other feeder to start feeding. I was so relieved! I had visions of it having been there all night, dehydrated..... but clearly it hadn't been.
7 weeks old today.