The hydro-filter is a small simple household sewage filtration device. A small, modular way to make ideas artificially. Able to adapt to a variety of gutter types and installed in gutters next to the street. In addition to making the sewage treatment system more integrated into nature and our lives. At the same time, the work of the current water purification field is shared, and the phosphorus and nitrogen are initially decomposed, so that the water purification plant has the spare capacity to treat other harmful substances.Solve the problems of gradually large population in the future.