PROBLEM TO BE SOLVED: To provide a shell group floating larva breading water agitation apparatus capable of reducing the physical damage which is given to the floating larva by the agitation apparatus, when a shell group floating larva having a body length exceeding 300 μm is agitated without agitation together with breading water.SOLUTION: In a breeding water bath 1 for breeding a shell floating larva a, there is arranged an agitation apparatus 2 comprising a water passage 3 having a pair of water introduction water ports 31 at opposing portions, and stirrers 4 having a rotary wing 41 made of a single wing of a single-leaf in said water passage 3, and a physical damage to be applied by said agitation apparatus 2 to a floating larva a having a body length 300 μm or more is agitated without air communication.SELECTED DRAWING: Figure 1【課題】 体長300μmを超える介類浮遊幼生を飼育水ごと無通気撹拌する際に、浮遊幼生に撹拌装置が与える物理的損傷を軽減することのできる介類浮遊幼生飼育水攪拌装置を提供する。【解決手段】 介類浮遊幼生ａを飼育する飼育水槽１内に、相対向する箇所に一対の導水口３１を有する水路３と、該水路３内部に単葉１枚からなる回転翼４１を有する攪拌器４とを備えた撹拌装置２を配置し、体長300μmを超える介類浮遊幼生ａを飼育水ごと無通気撹拌する際に、介類浮遊幼生ａに上記撹拌装置２が与える物理的損傷を軽減する。【選択図】 図１
