If you don't have a strong plankton community esp zooplankton species diversity,,,, GSH will not thrive. Also if you don't have adequate weed habitat and woody cover habitat at 20%-25% of the pond shoreline area then GSH will struggle to maintain good numbers with a strong LMB population. Also if the pond does not have lots of small 3"-5" BG the shiners will struggle to survive long enough to get to 5"-6" long.

Maybe better than buying GSH as forage reduce the number of foxes in your chicken coop. LMB are usually over crowded in ponds creating the perceived notion there is too little forge fish present when in reality there are too many predators, over eating the pond productivity resulting in not enough food.