CHANNEL CATFISH POND EFFLUENTS

Water samples were collected four times a year for 2 years from the su rface and bottom of 25 ponds used for commercial culture of channel ca tfish (Ictalurus punctatus) in central and west-central Alabama. Sampl es were analyzed for 5-d biochemical oxygen demand (BOD5), nitrite-nit rogen, nitrate-nitrogen, total ammonia nitrogen, total Kjeldahl nitrog en, total phosphorus, soluble reactive phosphorus, suspended solids, v olatile solids, settleable solids, pH, and dissolved oxygen. Ranges fo r variables were as follows: BOD5, 1.9-35.54 mg/L; settleable solids, 0-1.8 mL/L; suspended solids, 5.2-336.7 mg/L; volatile solids, 0.02-22 1.0 mg/L; total phosphorus, 0-1.85 mg/L; soluble reactive phosphorus, 0-0.074 mg/L; total Kjeldahl nitrogen, 0.58-14.04 mg/L; total ammonia nitrogen, 0.008-8.071 mg/L; nitrite-nitrogen, 0.001-1.410 mg/L; nitrat e-nitrogen, 0-6.661 mg/L; dissolved oxygen, 0.8-16.8 mg/L; and pH, 4.9 -9.5. Concentrations of water quality variables were skewed towards th e lower ends of these ranges. Occassionally, concentrations of some va riables were higher than those normally encountered in natural streams and exceeded recommended effluent concentration limits.