PROBLEM TO BE SOLVED: To provide a water tank enabling breeding of Japanese glass shrimp, firefly squid, etc., for a long period.SOLUTION: The water tank is provided with a tank body 1, a water-supply pipe 3 and a draining pipe 5. The tank body 1 has a circular or polygonal cross section and a bottom 2 of the body is inclined to gradually deepen toward the center. The water-supply pipe 3 has a water injection port 4 ejecting water toward the center of the bottom 2 of the tank body 1, and the draining pipe 5 is vertically placed at the center of the tank body 1 and a plurality of water-sucking ports 6 to suck water in the tank body 1 are opened on the draining pipe along the longitudinal direction of the draining pipe 5.COPYRIGHT: (C)2011,JPO&INPIT【課題】 白エビやホタルイカ等を長期間飼育できる水槽の提供。【解決手段】 水槽本体1と、給水管3と、排水管5とを備え、水槽本体1は、横断面が円形又は多角形であると共に、底面2が中央に向かって次第に深くなるように傾斜しており、給水管3は、水槽本体1の底面2の中央部に向けて水を噴射する水噴射口4を有し、排水管5は、水槽本体1の中央部に鉛直に設けてあり、水槽本体1内の水を吸い込む水吸い込み口6が長手方向に複数設けてある。【選択図】 図1
