• 한국수산과학회지
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• 제52권2호
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• pp.159-172
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• 2019

This study investigated the effects of dietary monobasic potassium phosphate (MKP) on the growth of the far eastern catfish Silurus asotus and four leafy vegetables in a hybrid biofloc technology aquaponic system. To an experimental diet containing 45% protein and 7% lipid, 1, 2, 3 or 4% MKP was added and was designated as MKP1, MKP2, MKP3, and MKP4, respectively. The optimum MKP levels were determined for the growth of fish and four leafy vegetables over 10 weeks. After the 10-week feeding trial, weight gain, feed efficiency, specific growth rate and protein efficiency ratio were higher in the fish groups fed MKP2 and MKP3 than in the other groups (P<0.05). The growth of the four leafy vegetables was also higher in the fish groups fed MKP2 and MKP3. Water quality [dissolved oxygen, pH, water temperature, electrical conductivity, turbidity, total ammonia nitrogen (TAN), $NO_2-N$, $NO_3-N$ and $PO_4-P$] was measured six times a week using a portable water quality meter and reagent measurements. The TAN (4.58-20.40 mg/L), $NO_3-N$ (24.12-52.40 mg/L) and $PO_4-P$ (20.38-48.48 mg/L) levels increased with time, while the $NO_2-N$ level remained below 0.1 mg/L throughout the study.