PROBLEM TO BE SOLVED: To provide a water tank for aquarium fish which can prevent displacement of, e.g., the heating unit of an electric heater placed as an underwater device in water in the body of the water tank and has beautiful appearance.SOLUTION: A filter-housing space 6 is made in the water tank body 2 of the water tank 1. The filter 20 is housed and placed in the filter-housing space 6 to be taken out in a state in which at least the lower part of the filter is soaked in water 40 in the water tank body 2. Between the filter 20 and a space-forming wall 6A forming the filter-housing space 6, a first passage 51 comprising the space between both 6A and 20 and through which the electric power cord part 61b of the electric heater 61 is passed is formed. Moreover, one end opening 51a of the first passage 51 is arranged at a position downward of the water surface 41 of the water tank body 2 so as to face the inside of the water tank body 2, while the other end opening 51b of the first passage 51 is arranged at a position upward of the water surface 41 in the water tank body 2.COPYRIGHT: (C)2013,JPO&INPIT【課題】水槽本体内の水中に配置される水中装置として例えば電気ヒータの発熱部の位置ずれを防止することができ且つ美観が良好な観賞魚用水槽を提供すること。【解決手段】水槽1の水槽本体2内に濾過器収容空間6が設けられている。この濾過器収容空間6内に濾過器20が少なくともその下部が水槽本体2内の水40中に浸漬される状態に取り出し可能に収容配置されている。濾過器収容空間6を形成する空間形成壁6Aと濾過器20との間に、両者6A,20間の隙間からなり且つ電気ヒータ61の電源コード部61bが通される第1通路51が形成されている。さらに、第1通路51の一端開口51aが水槽本体2内の水面41よりも下側の位置に水槽本体2の内側に臨んで配置される一方、第1通路51の他端開口51bが水槽本体2内の水面41よりも上側の位置に配置されている。【選択図】図5
