PROBLEM TO BE SOLVED: To provide a hydroponic device capable of: reducing weight of a culturing tank preventing leakage of nutrient upon breakage reducing cost eliminating the need for disposing used rock wool and water-permeable root barrier sheet achieving sufficient supply of nutrient to a nursery plant and simply determining the position of a planting float in an intermediate section of a liquid storing space in a width direction.SOLUTION: The hydroponic device comprises: a culturing tank made of foamed synthetic resin a planting float floating on a nutrient surface in a liquid storing space water leakage preventing resin film which covers a formed wall on the liquid storing space and determines the position of the planting float in the intermediate section of the liquid storing space in a width direction water-absorbing sheet which is placed on the planting float and whose end part is arranged under the nutrient surface and a plug nursery plant without rock wool placed on the water-absorbing sheet. The water-absorbing sheet includes a lower part water-absorbing sheet and an upper part water-absorbing sheet which covers the plug nursery plant from upward. Both of the part water-absorbing sheets are made of nonwoven fabric having a three layered structure in which an intermediate layer comprising pulp short fiber is arranged between a first surface layer and a second surface layer which are made of synthetic resin short fiber so that the short fibers are interlaced.COPYRIGHT: (C)2014,JPO&INPIT【課題】栽培槽の軽量化を図り、破損時も養液の漏出を防ぎ、低コスト化が図れ、使用済みロックウールの産廃処分や透水防根シートが不要で、苗への養液供給を充分に行えて定植フロートを貯液空間の幅方向の中間部に簡単に位置決め可能な水耕栽培装置を提供する。【解決手段】発泡合成樹脂の栽培槽と、貯液空間の養液面に浮かぶ定植フロートと、貯液空間の形成壁を被覆し、定植フロートを貯液空間の幅方向の中間部に位置決めする漏水防止用樹脂フィルムと、定植フロートに載置され、端部が養液面下に配置される吸水シートと、ロックウールを含まず、吸水シートに載置されるプラグ苗とを備え、吸水シートは、下側部分吸水シートと、プラグ苗を上方から覆う上側部分吸水シートとからなり、両部分吸水シートは、合成樹脂短繊維製の第1の表面層と第2の表面層との間に、パルプ短繊維を含む中間層を、短繊維が交絡するように配置した3層構造の不織布からなる。【選択図】図1
