Fish husbandry system

Claim 1

In a fish husbandry system for the large scale raising of fish for human consumption of the type including one or more series-connected water filled tanks containing fish at a high density, with the water flow in each tank being from bottom to top at a predetermined rate, an inflow of feed water to the system being through an inlet conduit leading into the top of a downwardly divergent hood in at least one of the tanks, the lower end of the hood being in fluid communication with the water in the lower end of said tank, oxygen gas being injected into the water flowing through the hood to cause a large proportion of said gas to be dissolved in the water for maintenance of a desired level of oxygen in said tank for the raising of said fish, the improvement comprising constricted throat means interposed between said inlet conduit and the top of said hood for regulating the velocity of inflow of water into said hood within predetermined limits for optimum dissolution of said oxygen in said water, at least a portion of said throat means having an internal diameter less than that of said inlet conduit.