Water tank for aquaculture

The water tank comprises a water tank body, a water conveying pipe is arranged above the water tank body, a water outlet is formed in the bottom face of the water tank body, the processing assembly is arranged in the water tank body and comprises a water supplementing assembly fixedly installed in the water tank body, and an anti-blocking assembly is arranged below the water supplementing assembly. When impurities in the water tank need to be filtered, the impurities can be filtered through a filter plate, when the water level of a floating ball drops, a pull rope fixedly installed on the outer wall of the floating ball moves along with the floating ball to drive a first magnetic block fixedly installed at the end of the pull rope to move along with the floating ball, and when the first magnetic block and a second magnetic block attract each other magnetically and the floating ball moves downwards, the first magnetic block and the second magnetic block attract each other magnetically. The water conveying pipe