Snipe, thanks for the additional info. I thought that was the case - you can't have a "refuge" if small, efficient predators can also occupy the same space.

However, that leads to additional questions for a possible "Plan B".

Basically, is it economically feasible to have a FHM only forage pond at a higher elevation than your main pond and periodically open a 6" pipe to drain in FHM?

Or, is the nutritional value of the commercial fish foods such a better deal to feed a BG/LMB pond, that you should just optimize that option and not waste the effort managing forage?