I have fished farm ponds 95% of my fishing time since grade school & I am now 66. Bass & 'gills in ponds. Crappie only in larger waters. A key is selective harvest, which I practice & I catch a LOT of 9"-10" 'gills yearly with an occasional 11 incher thrown in. I would recommend getting on http://www.pondboss.com/ to learn about pond management.