the thing about any commercial pre mixed mineral is they are formulated for goats across the country. So they put the mininum in there for any area. So i live in a low copper and selinium area. The company doesnt want to overdose any goat, so they put the mininum amount for an area that isnt deficiant. I love purina goat mineral ( its the only product that i do like that they make) I have to give selenium as well as copper throughout the year. What i do is open the big cow bolus with the rods in them. I dump theminto a plastic baggy, and have it in the bucket on top of my other mineral. When i see a fish tail or a off color on a goats thighs i give them a pinch. rather then dosing the whole herd at a specific time i does when need and by who is needing it.