Ed - I think the HSB in the low density cage will tend to keep the free ranging HSB nearby those in the cage. Also if you build a cage for the HSB be sure it is a cylindrical cage not a square or rectangular cage. Research has shown that better results of survival of HSB occurs when cylindrical cages are used. Cylindrical cages are not as important when other species are grown in cages. If you use an automatic feeder you can build or adapt a baffel to keep feed from being thrown beyond the range of the cage. However pellets drifting across the cage will also provide food for the caged fish. Feeding activity of caged fish will provide a feeding stimulus for free ranging HSB and other fish.

I would think twice and be careful of leaving fish caged and somewhat unguarded as you describe. If word "gets out" you could lose many fish.

PS Another pondowner near me is establishing a new pond with HSB and y.perch. We can compare notes.

aka Pond Doctor & Dr. Perca Read Pond Boss Magazine -
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