Hello!
I recently got chicks and they are 4 weeks old now

The biggest problem I found with them was probably keeping their brooder clean. The chicken waterers they tell you to buy are a total disaster don't buy them!!
After a few odd attempts, (rags underneath, a small box placed under it) nothing worked to keep the chicks from kicking up their feed and pellets into the water dish. Aka I was replacing their water every 30 minutes it seemed.
I finally bought two $5 hamster water bottles at a small store in town. And they work AWESOME!
I've zip tied small shot solo cups underneath to catch the slow drip. The chicks sometimes just drink out of the cups. Before you leave them with the new water bottles tap the ball and let them see water comes out.
If you have more than 5 chicks I'd get 2 bottles.
Ive heard that "pasty butt" is an important issue that is very common. I haven't experienced that with my 10 chicks but they've also been on Apple cider vinegar since they were a few days old. I add 2 tbs of it to their water, as well as a tsp of chick probiotic to their water.
Also I add grinded up oats to their food! They love it!
Good luck!! This site is wonderful for any chicken people!