Effects of Immediate Oxygen Supplementation (Sodium Carbonate and Hydrogen Peroxide) on Water Quality Parameters, Behavioural Responses and Survival of Puntius sophore Fingerlings

The intensification of aqua‐farming practices has increased the need for a constant oxygen supply to avert oxygen depletion and unexpected fish mortality in captivity. This study assessed the effects of bio‐ox (10% sodium carbonate and hydrogen peroxide) as an immediate oxygen booster on water quality, behavioural patterns and cumulative per cent survival (CPS) of Puntius sophore (3.50 ± 0.13 g) in a controlled rearing environment. The completely randomized design comprised four treatments: a control group (T1) without bio‐ox and three experimental groups (T2, T3 and T4) treated with 1, 3 and 5 g of bio‐ox per 70 L of water, respectively. Bio‐ox was applied at the start and at 36 h, with observations recorded every 6 h. Initially, water quality parameters showed no significant differences ( p > 0.05) among treatments. Post‐supplementation, bio‐ox levels significantly influenced ( p < 0.05) hydrological variables, including conductivity, total dissolved solid (TDS), total ammonia nitrogen (TAN), dissolved oxygen (DO) and pH. Conductivity and TDS increased with higher bio‐ox dosages, whereas TAN levels were significantly lower ( p < 0.05) in all bio‐ox–treated groups compared to the control, with no significant differences among treated groups at 42, 48 and 54 h. DO peaked at 11.90 ± 0.10 mg/L at 60 h in T4, whereas T2 maintained optimal levels. The pH also varied significantly ( p < 0.05), reaching a maximum of 9.23 ± 0.01 at 36 h in T4. Temperature, water pressure and salinity remained unaffected ( p > 0.05). Behavioural observations indicated minimal abnormalities in T2, whereas higher bio‐ox doses (T3 and T4) resulted in pronounced changes, including hyperactivity, abnormal swimming and convulsions. Kaplan–Meier survival analysis revealed significant differences among treatments, with T2 showed the highest CPS of 66.7%, which was significantly greater than that of T3 (26.7%, p = 0.026) and T4 (13.3%, p = 0.007). The control group T1 (40%) exhibited intermediate survival rates, which were not significantly different from any treatment groups. These findings suggest that bio‐ox at 1 g/70 L (T2) provides optimal conditions, stabilizing fish behaviour and significantly improving survival compared to higher doses.