Chickens normally have 2 kinds of poop. One looks more solid, and one looks more runny. both are normal. Here is an article with pictures (ewww), but very helpful.
Just be sure the poop isn't sticking to their little butts, clogging the poop hole - that is pasty butt. You need to gently clean that off so they are not clogged up. That will kill a chick.
Article with pictures on how to care for pasty butt. It's most often caused by stress, so giving your birds electrolytes and probiotics (yogurt and fermented chick mash) are good ways to help reduce or prevent this.