How long do Chicks need to be on Chick Starter?

[Mama Hen of 4]

I have starter/grower feed which was told by the feed store that they can have that from 1 day to 18-20 weeks, then switch to layer feed. I stopped giving mine food in the brooder at night at 5 weeks, just water. There was so much wasted feed at the bottom of the brooder. I have them in a temporary pen outside during the day, with food and water, while they’re permanent run and coop is getting ready. Then back in the brooder in the evening. They should be ready to move into the coop/run set-up at 6 weeks.

 

[Altairsky]

I don't know why in my country everything is more complicated. We have 2 different types of chick starter: The first stage, and the second stage. The first stage chick starter is for hatchling, 'till 30-40 days. Then from 30-40 days old to 5 months it's 2dn stage chick starter. After 5 months it's layer feed.
For meat chickens there is only 1 type of feed to give them from the day they hatch to the freezer day.