PROBLEM TO BE SOLVED: To provide a water treating device that is downsized, applicable to existing breeding environment, and appropriate for culture of aquatic organisms and plants.SOLUTION: There is provided a water treating device comprising a water receiving tank 10 for temporary storing water for processing from a water source, a biological treating tank 20 for biologically treating water of the water receiving tank 10, and a balancing tank 30 discharging water to the water source after storing the biologically cleaned water treated in the biological treating tank 20, wherein the biological treating tank 20 is provided with one or more helical microorganism attached carrier 21, and the balancing tank 30 is provided with a microbubble line 40 that returns microbubble-containing water, generated by making the cleaned water to generate microbubbles, to the water receiving tank 10.【課題】 コンパクトでなおかつ既存の養育環境にも適用可能な水棲生物や植物の栽培に適した水処理装置を提供する。【解決手段】 水浄化装置は、処理する水源からの水を一時貯留する受水槽１０と、受水槽の水を生物処理する生物処理槽２０と、前記生物処理槽で生物学的に浄化された水を貯留した後、前記水源に放流する調整槽３０と、を備え、生物処理槽２０は、１以上の螺旋状微生物接触担体２１を備え、そして調整槽３０は、浄化された水に微細気泡を発生させ発生した微細気泡含有水を受水槽１０に戻す、微細気泡ライン４０を備えている。【選択図】図１
