There were two species of sunfish I was interested in, one being the central longear sunfish 7-8" max size supposedly, and the Western dollar sunfish max 5". Do you think the western dollars would be to small? If I go with the central longear how many would you recommend for a 120g.
Western Dollar is definitely too small, Central Longear is questionable, ;but to be on the safe side it would probably be better to go with Pumpkinseeds or Redbreasts if you want a large sunny with color, and no you can raise them together; I would make sure the sunfish is a little larger (but not too much) than the Bullhead because Bullheads grow larger.
Stonecats are also good with Sunnies, but Im not sure how a Bullhead would react to one.