Provided are a water quality purification device, a water purifier and an aquarium that use the water quality purification device. The water quality purification device includes a component filled with a micro-electrolysis catalyst (1) and a biological filtration component (2) that are connected in series. By utilizing a micro-electrolysis technology, pollutants in water are pre-processed and the biodegradability of the water is improved. A water body processed by the micro-electrolysis catalyst (1) enters the biological filtration component (2), which can greatly improve the purification efficiency of the biological filter bed. Working together with an adsorption electrode (4), this structure can effectively stabilize the water quality in the aquarium and greatly reduce the required times of changing water.
