Method for collecting blue algae and purifying water quality

The invention discloses a method for collecting blue algae and purifying water quality by breeding algae-eating fishes in a water body. The method provided by the invention is characterized in that a plurality of uniformly distributed net cages used for breeding algae-eating fishes are arranged in an algae-controlling water area; the bottom of each net cage is equipped with a fish manure collector which is made from a dense net; the algae-eating fishes are bred in the net cages; and an algae manure interception net is arranged on the edge of the water area in which the net cages are disposed.According to the invention, the algae manure interception net, a fish-interception and blue algae-capture module and an ecological floating-island water quality purification module are arranged in local water areas, so as to effectively control the biomass of blue algae in water source areas, effectively reduce the content of N and P in a water body, improve the safety of water consumption, and obtain the cycling support