Bruce,
I know of no one who has taken the time to try to condition redear to eat artificial food. It's too much work for little pay. Redear are traditionally used as an "insurance" policy for diversification of forage fish populations and to manage invertebrate infestations. So far, there hasn't been sufficient motive for a commercial producer to figure it out.

Teach a man to grow fish...
He can teach to catch fish...