Asian Journal of Environment & Ecology

Aims: To evaluate and compare the length-weight relationship and modified condition factor of rohu (Labeo rohita, T₁) and Mozambique tilapia (Oreochromis mossambicus, T₂) reared in a floating-raft aquaponics system.

Study Design: Comparative experimental evaluation of biometric performance and body condition of two fish species under floating-raft aquaponics conditions.

Place and Duration of Study: Research Laboratory (Wet Lab), Department of Aquaculture, College of Fisheries, Maharana Pratap University of Agriculture and Technology, Udaipur, Rajasthan, India, for 60 days.

Methodology: One hundred fingerlings of each species were stocked separately in 400-L fibre-reinforced plastic tanks integrated with tomato (Solanum lycopersicum) saplings on floating rafts. Total length and body weight were recorded to establish the length–weight relationship using the power function W = aLᵇ. The coefficient of determination (R²) and regression coefficient (b) were estimated through log-transformed linear regression, and the modified condition factor (K) was calculated from the estimated b value.

Results: A positive length–weight relationship was observed in both species. The coefficient of determination was higher in L. rohita (R² = 0.8554) than in O. mossambicus (R² = 0.7432), indicating a stronger length–weight association in rohu. The b values were 1.9681 and 1.8742, respectively, indicating negative allometric growth in both species. The relationships were statistically significant (p < 0.05). The modified condition factor was higher in L. rohita (2.94) than in O. mossambicus (1.95).

Conclusion: Both species performed satisfactorily under the tested floating-raft aquaponics conditions, with L. rohita showing a stronger length–weight relationship and higher modified condition factor than O. mossambicus. These findings demonstrate the feasibility of rearing both species in floating-raft aquaponics, with rohu exhibiting comparatively better biometric performance.