You have a few Leopard Discus it looks like.. and the good thing is they are still coloring up so they aren't stunted that's for sure.. The Pigeon Bloods though.. I see you have 2 of them.. Its hard to tell from the one in the back but your first picture that pigeon is deff stunted.. He will still grow but im not sure how big he will get.. he wont get max size though.. The rest of them look good to me. I really like that Leopard discus in the 2nd pic
Discus are always stressed from shipments.. It can take them weeks to act normal. So them hiding or not eating is normal for the most part at least to a degree.
What kind of foods are you feeding them and are they all eating ? Or do you have some that are spitting food out or wont eat at all ? Also what is the temperature of the water, and you need to do daily or every 2 days water changes.. How big is this tank again ? Depending on the size you will want to do at least 50% water change every day, or 70-80% every 2-3 days like I do.. You need to keep the water clean and fresh, and nitrates 20 or lower. If the nitrates get too high it stresses them out and they can turn dark. Same with the temps if they are too low it can stress them out. They need to be fed at least 3 times a day.. At least.
I have discus that like tetramin flakes, most of mine love beefheart, and they all like bloodworms too, Freezedried bloodworms they will eat but hesitantly. So I feed my discus 3 types of foods.. 2x a day beef heart with 2x cubes of frozen blood worms, and then I feed them flakes 1 time a day.. So in total 3 feedings, with 3 types of foods.
Also the strains I see you have are.. 2x Pigeon Bloods, 1x Blue Turquoise, and 2x Leopard Snakeskin Discus. The last one on your first set of pics where he looks a little green and dark.. I cant tell what he is