I know that brine shrimp has no real nutritional value for our fish, but is enriched brine any better? I have a copperband who is currently being sustained by enriched brine and selcon. My concern is the longrun with the copperband.
A varied diet is best in the long run. Enriching the brine shrimp with Selcon will add vitamins, but you should also consider trying some other food types. Have you tried to feed it any kind of pellets, flakes, frozen mysis shrimp, live mysis shrimp, etc.? I feed our tank a rotation of Selcon enriched live brine shrimp, pellets, and Selcon soaked frozen mysis shrimp, plus there's a breeding population of live mysis in our tank.