I currently have a 65g tank with one young warmouth, three blacktail shiners (will be removed soon), and six longear sunfish. Two of the longears have grown since I've gotten them, four haven't increased in size much at all.
My concerns here are:
1: Between the two dominant longears (they seem to both be males), at least 3 cubic feet of space is completely occupied, and the four small longears have to avoid those places in order to not be chased.
2: Those four should be growing, they're only about 3" each. They're eating plenty, so it's probably stress keeping them from growing.
Male sunfish are jerks, and I'm worried the little guys will get hurt running into things. Some of them are already a bit scuffed up from running into sticks while trying to get away from the bullies.
3: The warmouth was something I didn't plan for, since I didn't even know we had those, but I caught one and he was too pretty and neat to not keep. With his addition, it seems like the tank will be overstocked if/when everything reaches full size.
4: Both dominant longears have established clear territories, and they don't even see each other most of the time, thanks to a wall of plants between their nests. If I remove the four being chased, will these two continue to not notice each other and therefore not fight?
5: The biggest male has established one spot as his, and he totally ignores anything that's not in his spot. The smaller ones all know to avoid him. I don't think dither fish are needed to keep the big male from attacking anything. Does that seem about right?
6: Will longears continue to have bright colors if there are no females in the area to show off to? I think I've seen solitary longears that are nice and bright...
7: If I make space in the aquarium, what other fish could I keep, considering the warmouth? Would adding a tadpole madtom risk having the warmouth try to eat it and choke? In general, how big does a fish have to be for it to be warmouth-proof, assuming the warmouth doesn't quite reach maximum size? Assume a 7-8" warmouth.
8: If I give the four subordinate longears to someone, would they possibly form a reasonably stable community in a properly sized tank, or would they have to add a few more longears to keep everything stable?