PROBLEM TO BE SOLVED: To provide hydroponics apparatus in which fish can freely swim between cultivation beds installed in multiple stages in the vertical direction.SOLUTION: A drain pipe 12 for connecting an upper cultivation bed 11 and a lower cultivation bed 11 is configured so that its upper end portion opens at a position which is a peripheral portion 11b of the upper cultivation bed 11 and which is lower than the water level, its lower end portion opens at a position which is a peripheral portion 11b of the lower cultivation bed 11 and is lower than the water level, and the whole is curved in an arc shape or a spiral shape to allow fish F to pass. The fish F of the cultivation bed 11 in the lower stage enters inside from the lower end portion of the drain pipe 12, goes upstream in the drain pipe 12 having gradually going-up inclination, and travels to the upper cultivation bed 11. The fish F of the cultivation bed 11 in the upper stage enters inside from the upper end portion of the drain pipe 12, goes downstream in the drain pipe 12 along the stream of a water W, and travels to the lower cultivation bed 11.SELECTED DRAWING: Figure 1【課題】上下方向に多段に設置された複数の栽培ベッド間を、魚が自由に行き来できる水耕栽培装置を提供する。【解決手段】上段の栽培ベッド１１と下段の栽培ベッド１１を連結する排水管１２を、その上端部が、上段の栽培ベッド１１の周部１１ｂであって水位よりも低い位置に開口し、その下端部が、下段の栽培ベッド１１の周部１１ｂであって水位よりも低い位置に開口し、全体が円弧状または螺旋状に湾曲していて、魚Ｆの通過を許容するように構成する。下段の栽培ベッド１１の魚Ｆは、排水管１２の下端部から内部へと入り込み、緩やかな上り勾配の排水管１２を遡上して、上段の栽培ベッド１１に移動する。上段の栽培ベッド１１の魚Ｆは、排水管１２の上端部から内部へと入り込み、水Ｗの流れに沿って排水管１２を下降して、下段の栽培ベッド１１に移動する。【選択図】図１
