Fish bioassays for evaluation of raw and bioremediated dairy effluent

Short-term static bioassays were conducted for raw and bioremediated dairy effluent with rohu, Labeo rohita to substantiate its usability for fish culture. The 96-h LC50 of the raw effluent was 25.5% (i.e., 74.5% dilution). After stabilisation, sedimentation and bioremediation with Wolffia for 15 days the effluent showed a decline in toxicity and the 96-h LC50 was calculated as 73.5% (i.e., 26.5% dilution). Based on this, the dairy effluent could be used in pisciculture as a fertilizer with proper dilution.