<；P>；PROBLEM TO BE SOLVED: To provide a water treatment apparatus and a water treatment method which can prevent waste of water and energy. <；P>；SOLUTION: The water treatment apparatus 87 includes: a rapid filtration tower 60 to which culture water containing nanobubbles are supplied and which is filled with filter sand 106 and a filter medium 107 for neutralization； and a slow filtration tank 67 to which the culture water having been filtered in the rapid filtration tower 60 is supplied, and which is filled with a bacteria filter medium 108 and a filter medium 109 for neutralization, and filters the culture water at a slower rate than that of the rapid filtration tower 60. Thus, the detergent power of the nanobubbles can prevent the filter sand 106 and the filter medium 107 for neutralization from clogging in the rapid filtration tower 60, and prevent the bacteria filter medium 108 and the filter medium 109 for neutralization in the slow filtration tank 67 from clogging. As the surfaces of the filter medium 107, 109 for neutralization are washed and oxidized by the detergent power and oxidizing power of the nanobubbles, the neutralization of water can be reasonably performed by eluting minerals, such as calcium, from the filter medium 107, 109 for neutralization. <；P>；COPYRIGHT: (C)2010,JPO&INPIT
