PROBLEM TO BE SOLVED: To provide a hydroponic device in which growth of Microcystis is controlled.SOLUTION: A hydroponic device: comprises a box-like nursery bed case for containing nutritious liquid and a nursery bed panel provided over the nutritious liquid of the nursery bed case and having a plurality of holes for settled planting to determine the positions of vegetables to be grown； and is characterized in that at least one of the nursery bed panel and the nursery bed case is provided with, around a gap formed therebetween, light incident-preventing means for preventing light from entering into a liquid surface of the nursery liquid from the gap.【課題】アオコの発生を抑制することができる水耕栽培装置を提供すること。【解決手段】養液を収容する箱状の苗床ケースと、この苗床ケース内の養液上に設けられて育成すべき野菜の位置を定める複数の定植孔を有する苗床パネルとを備え、前記苗床パネルと前記苗床ケースとの少なくともいずれか一方が、それらの間に形成される隙間の周辺一帯に、前記隙間から前記養液の液面への光の入射を阻止する光入射阻止手段が設けられていることを特徴とする水耕栽培装置。【選択図】図７
