My four are 7 weeks today and in their coop and doing well. I'm running low on their "Purina premium start and grow medicated feed". I am reading conflicting things about a grower feed. Am I supposed to find something that's just a grower feed? Or shoud I keep them in this stuff? I didn't know if there was a difference between chick starter and grower that can be purchased on their own or if they are one in the same. TIA!