Any thoughts on Southern States vs Tractor Supply brand feed ? I have been using Tractor Supply for a couple of years and still need to supplement the calcium. I frequently get a soft egg shell. Can anyone offer some insight to getting harder shells? I think the girls are lacking calcium even though they have full-time access to crushed oyster shell and occassionally cheese. Is there really a brand that can provide all the nutrients they need? Has anyone tried the bag of Omega supplement at Tractor Supply?