As CJ says that will help. Yes you can sub some small BG for the adults it just takes more. Standard stocking #s for adding intermeiate size (4-5 inch)BG to a pond with adult LMB is 100 per acre. I would stock the FH and GShiners as CJ said and add 1000 small 2 inch BG. Out of those small BG you may get a 10% survival to 5 inches by winter. That would go a long way toward helping. I would in addition place my order for 200 5 inch BG for fall.