To provide a peculiar installation tool capable of executing easily, even rearing of eel by a closed type circulation filtration method with many merits, although rearing of eel is difficult.SOLUTION: There is provided a filtration lid-shaped installation tool on an upper part of a scupper 2 on a bottom of an eel rearing water tank 1, in which straight rod bodies 3a whose cross section is formed into an almost reversed triangular shape or reversed trapezoidal, whose upper side is horizontal and whose both sides are widened upward and tapered, are arranged in parallel in a state of aligning upper surface heights thereof, the straight rod bodies are arranged in a striped shape with a gap for preventing white bait passage, thereby forming a screen-shaped installation tool 3 for scupper in the eel rearing water tank. In addition, a block plate 4 is provided above the installation tool 3 for scupper at a prescribed interval.SELECTED DRAWING: Figure 2【課題】多大なメリットのある閉鎖型循環濾過方式による飼育を、難しいとされる鰻においても難無く実施できるような独特の設置用具を提供すること。【解決手段】鰻の飼育水槽１の底部にある排水口２の上部に設ける濾過蓋状設置具において、断面が略逆三角形ないし逆台形状で上辺が水平かつ両側辺が上広がりテーパとなる直棒体３ａを、多数平行にかつ上面高さを揃えて、シラス通過を妨げる隙間を隔てて縞状に配設して、鰻飼育水槽におけるスクリーン状の排水口用設置具３とする。更にその排水口用設置具３の上に所定間隔を隔てて遮光板４をセットしたものとする。【選択図】図２
