Fishpond water purifying device

The utility model discloses a fishpond water purifying device which comprises a shell, a water purifying device, a water purifying device and a water purifying device. The shell is internally provided with a filtering cavity with an opening in the top. The first filter cotton is arranged in the filter cavity and is in interference fit with the filter cavity; the filtering box is detachably arranged at the top opening of the filtering cavity, a first containing cavity with the top opening is formed in the filtering box, and a first draining hole is formed in the bottom of the filtering box; the second filter cotton is arranged in the first accommodating cavity and completely covers the first draining holes. By means of the structure, water entering the fishpond water purifying device needs to flow through the first containing cavity firstly and then can enter the filtering cavity, when the water flows through the first containing cavity, pollutants in the water are attached to the second filtering cotton in a