[PROBLEMS] To eliminate the need for pretreatment water tanks, chemicals, neutralizing agents, etc. by physically killing harmful enemy water creatures during water supply, and to supply the intake water as it is to the breeding tank. A porous nozzle for killing aquatic creatures is provided. An inlet side opening portion 2 having a diameter reduced from the inlet opening toward a throat portion 3 at the center of the hole, an outlet side opening portion 4 having a diameter increased from the throat portion 3 toward the outlet opening, and a minimum inner diameter. This is a perforated nozzle A for killing enemy water creatures provided with three or more nozzle holes 1 adjacent to each other. The entrance side openings 2 of the adjacent nozzle holes 1 are provided at a distance that interferes with each other. A partition wall 5 of the interference portion 6 of the entrance side opening 2 is cut out in a U shape, and a remaining portion 5a between the adjacent U-shaped cut portions 5b is formed in a sword tip shape. [Selection] Figure 6【課題】給水中に害敵水生々物を物理的に殺滅することにより、前処理水槽、薬剤、中和剤などが不要となり、取水した水をそのまま飼育水槽に給水することができる害敵水生々物殺滅用多孔ノズルを提供する。【解決手段】入口開口からから孔中央の喉部3に向かって縮径した入口側開口部2と、前記喉部3から出口開口に向かって拡径された出口側開口部4と、最小内径の前記喉部3とで構成されたノズル孔1が3個以上隣接して設けられた害敵水生々物殺滅用多孔ノズルAである。隣接するノズル孔1の入口側開口部2が互いに干渉する距離に設けられている。入口側開口部2の干渉部分6の隔壁5がU形に切除されており、隣接する前記U字形切除部分5bの間の切残し部分5aが剣先状に形成されている。【選択図】図6