Forage base might be an issue, but if I recall, less fish go out of the outflow than most people think.
Without knowing more details, I would think that culling LMB and crappie should be a good move to start reducing some of the predator base to leave more food for fewer mouths.
Because cost is an issue, I wonder if it's worthwhile to put up some rot baskets to create maggots to feed the forage base.
Excerpt from Robert Crais' "The Monkey's Raincoat:" "She took another microscopic bite of her sandwich, then pushed it away. Maybe she absorbed nutrients from her surroundings."
