this is probably splitting hairs, but i haven't found any good facts on if every feed additive has "all" the minerals you need, whether this has a detrimental effect. In California, we have a problem with selenium and copper, so everything has it in it. the protein lick, the salt lick, protein pellets, premixed feed, mineral additives in "breeder pak". i have been not buying the "show" type mixes becuase it has all that stuff in it including potassium, Mg, Mn, etc that i provide with the Crystalyx western region lick, bloatguard block and mineral block. what do kidneys look like on all that, and can you smell or see differences in urine? plus, the $ for "peace of mind".