A wastewater treatment plant was converted for use as an aquaculture research facility. To compare the growth of hybrid tilapia in shallow and deep tanks, thirty sex-reversed hybrids of Oreochromis niloticus x Oreochromis aureus were stocked in three shallow tanks (1.47 m in diameter x 0.65 m in depth) and their growth was compared to 7,000 hybrids stocked in deep (8.5 m x 8.5 m x 4.0 m) tanks. Stocking density (1 fish/38L) was the same for all tanks. Winter growth in the small tanks ranged from 1.05 - 1.11 g/day compared to 0.802 - 0.844 g/day in the deep tanks. ANOVA's and Student-Newman-Keuls tests showed that the growth of the hybrids within the shallow tank replicates and deep tank replicates was not significantly different but there were significant differences between shallow arid deep tanks. When the temperature rapidly decreased to a low of 13°C and remained between15°C and 25°C during a winter cold snap, the rate of growth in all of the tanks decreased to 0.0 g/day. After three months, the fish were sorted into100 g groups and placed in separate shallow and deep tanks. The different sizes still grew at significantly different rates in the shallow and deep tanks. The low temperatures continued to be a major factor affecting growth, particular1y with the
| Date of Award | Jan 1 1999 |
|---|
| Original language | English |
|---|
| Supervisor | Bart Baca (Supervisor), Curtis Burney (Advisor) & Richard Spieler (Advisor) |
|---|