CLOSED CIRCULATORY CULTURE SYSTEM AND PH CONTROLLING DEVICE

PROBLEM TO BE SOLVED: To provide a closed circulatory culture system enabling the pH control without using an alkali agent and the culture of fish and shellfish without exchanging seawater. SOLUTION: The closed circulatory culture system cultures fish and shellfish in a culture tank 1 while cleaning and circulating the seawater in the culture tank 1. The system has an electrolytic cell 5 provided with an anode chamber 3 and a cathode chamber 4 partitioned with a separation membrane 2 and electrolyzing seawater supplied from the culture tank 1. The system further has a pH controlling device 100 having a neutralizing vessel 7 to neutralize the active chlorine in the seawater supplied from the anode chamber 3 with a carbonized agent 6, an air diffusion pipe 8 to blow air into the seawater in the neutralizing vessel 7 to aerate the water with the air and a mixing tank 9 to mix the seawater supplied from the cathode chamber 4 with the seawater supplied from the neutralizing vessel 7 and return the mixture to the culture tank 1. The pH control of the seawater in the culture tank 1 can be carried out by the electrolysis of the seawater without using an alkali agent. COPYRIGHT: (C)2006,JPO&NCIPI