We went in to TSC to purchase our first cornish rocks and the young man told us that the bin had a mix of cornish rocks and rhode island reds. We purchased the four remaining cornish rocks and the two supposed rhode islands. Once I got home, I look online and now know the RIR chicks were really female Gold sex links. So when the cornish rocks came in again last week, we purchased six more. Now we see a difference between some of the chicks, but we aren't sure if it is age or if it is because the first cornish rocks were really male sex links (which might make sense as they were in the same bin with the supposed RIR/real female gold sex links)? Does anyone know how to tell the difference? My dilemma is that the cornish rocks are supposed to go to 12 hour on/off feedings so I was already going to separate out the gold sex links and now I am not sure if I should separate all of the chicks I think are cornish rocks.... I've looked at pictures of both chicks....I've held old and new next to each other and besides weight I see no difference...my kids think the fat ones look like they have lighter legs than a skinnier one we pulled from the brooder (more orange)..I'm not sure I even see that.