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Four experiments with feed‐trained crappies Pomoxis spp. were conducted to enhance the knowledge of growing crappies as food fish. Two experiments compared growth performance of juvenile Black Crappies P. nigromaculatus and White Crappies P. annularis (1) between fish that were fed two locally available commercial feeds or (2) among fish reared at densities of 0.81, 1.62, 3.25, and 6.50 g/L. No significant difference in growth performance between species was detected. Performance was significantly affected by commercial feed, but survival and feed conversion ratio (FCR) were not. An inverse relationship existed between density and growth variables except final biomass, which had a direct relationship with density; survival rate was not different among density levels. For the third experiment, Black Crappie growth in light‐blue control tanks was compared with growth in environmentally enhanced tanks (150 L) that had top cover structure (TCS), bottom dark coloring (BDC), or a combination of both. Fish growth was not different between control and enhanced tank treatments but significantly differed between the TCS and BDC treatments. In the fourth experiment, growth was compared between hybrid crappies that were fed using 12‐ and 24‐h belt feeders. Fish that were fed by use of the 12‐h belt feeders had improved FCR relative to continuous 24‐h feeding. These experiments demonstrated that crappies can be cultured successfully indoors, with no difference in early growth between species. Additionally, crappie growth could be affected by tank environment and by feeding regimen.

Growth of selected crosses ?) of Lincoln University bluegill stocks were evaluated. The purpose was to test the commercial potential for reaching marketable size (227-340 g) within 2 years in an indoor water-recycle system and grow-out in ponds. Pond hatched young-of-year bluegill were reared in a 12-tank (719 L/tank) indoor water-recycle system. Fish were fed to satiation three times daily. Fish were weighed and measured for total length (TL), for a 120-d growth trial. Initial mean fish weight and TL were 28.0 6 15.8 g and 106 6 16 mm, respectively. Final mean weight was 119.4 6 54.9 g, and mean TL was 161 6 19 mm. Crosses were significantly different (P 0.05). Initial female weight averaged 82.1 6 32.5 g, and male weight averaged 158.6 6 45.5 g. Feed conversion ratio was 1.26, and survival was 99.4%. Specific growth rate (SGR) averaged 1.21%/d with a mean length increase of 0.5 mm/d. Fish were then marked by specific crosses with colored visible implant elastromer tags. Fish were stocked in four 0.04-ha ponds (N ¼ 600 fish/pond; density ¼ 15,000 fish/ha) for 129 d. Final mean weight of fish in the pond study was 228.3 6 71.7 g; mean TL was 200 6 15 mm. Crosses were not significantly different from each other (P . 0.05). Sexual dimorphism was more pronounced after pond rearing; females averaged 175.4 6 41.7 g and males averaged 284.0 6 54.4 g. Results indicate bluegill grown in indoor recycle systems may reach target weights of 227-340 g within 2 years with the use of out-of-season spawning and selective breeding. Forty-eight percent reached or exceeded the minimum target weight (227-340 grams). This study also suggests that removing females could increase the number of fish reaching target weight by 33%.

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