The present invention relates also ornamental fish, etc. without distortion, and provides the aquarium lighting device that can be dazzling without admiration from the water bath of the upper opening while lighting. The apparatus includes a transparent light guide plate 4 of the flat shape, which is located above the water tank 1, I and a lighting unit 5, which is placed in the outer portion of the water tank 1. The upper 5a of the base portion 4a and the lighting unit 5 of the transparent light guide plate 4 is connected to a substantially inverted L-shape, the tip portion of the transparent light guide plate 4 is is provided downward of the reflection plate 9. Illumination light of the illumination unit 5, it is possible to be reflected by the reflector 9 is passed through the transparent light guide plate 4 illuminates the water tank 1 from above. The lighting unit 5, a hook portion 10 which can be hooked from above is provided on the side 1d of the tank 1. .BACKGROUND【課題】照明しながら水槽の上部開口からも観賞魚等を歪み無く、かつ眩しく無く観賞できる水槽用照明装置を提供する。【解決手段】水槽1の上方に配置されるフラット形状の透明導光板4と、水槽1の外側部に配置される照明ユニット5とを備えている。透明導光板4の基部4aと照明ユニット5の上部5aとは略逆L字状に連結され、透明導光板4の先部には下向きの反射板9が設けられている。照明ユニット5の照明光は、透明導光板4を通過させて反射板9で反射させることで、水槽1を上方から照明する。照明ユニット5には、水槽1の側部1dに上方から引っ掛け可能なフック部10が設けられている。【選択図】図3
