Abstract
Oxygen consumption and COD of organic pollutants in feces and remaining feed in pen culture of yellowtail and red sea bream were analyzed. Remaining feed was divided into solid (>165μ) and liquid (<165μ) categories. Higher oxygen consumption and COD were obtained from liquid remaining feed (LRF) compared with solid remain ing feed (SRF) and feces.
The relationship between the rate of mean oxygen consumption of organic pollutants; R (θ) and water temperature (θ) during the bacterial growth phase for 6 hours (corresponding to a quarter tidal sojourn period) was examined. Oxygen levels were recorded continuously by polarographic oxygen sensor in closed systems at 15°C, 20°C, and 25°C. There was little difference between water temperature coefficients; Q01 of organic pollutants and kinds of feed supplied, but there was a marked difference between R (20) and kinds of organic pollutants loaded into waters.
The relationship between R (20) and COD was shown with the following formula: R (20) =0.052⋅COD. R (θ) was computed by the following formula: R (θ) = R (20) ⋅Q01 (θ-20) . R (20) of LRF, SRF, and feces were 26.9mg/g⋅h, 8.8mg/g⋅h and 4.2mg/g⋅h, respectively. Q01 of LRF, SRF, and feces were 1.064, 1.088, and 1.075, respectively.
