Bluespotted sunfish do well in NJ because they like their close relatives the banded and blackbanded sunfish like soft acidic waters with very heavy vegetation growth. Not really the same habitat a good SMB pond would be. NJ's Pine Barrens have many acidic soft bodies of water in them where these sunfish species do well.
RBS also feed on mollusks and are very capable of eating hard shelled organisms. A small sunfish possibly suited to SMB would be the orangespotted sunfish. I am sure Dave has experience with them. I don't have much as they aren't native to the eastern US. I just began experimenting with them when I bought some last year. There are other little known sunfish species that could be considered. I stocked a small number of longear sunfish into my pond. I will see how they perform. They max out around 8", with few getting over 6". Their close relative the dollar sunfish is even smaller, only reaching about 5". There is also the bantam, redspotted and spotted sunfish. They are more southern species, but are found about as far north as southern Ill., so should be adaptable to at least areas where RES could survive.
