Aquaclear Power FilterThe AquaClear Power Filter provides mechanical, chemical and biological filtration through its multi stage filtration system. The filter filtration volume is up to 7 times larger than comparable Filters. Preserves Beneficial acteria for a Stress Free Environment Patented Refiltration System for a Health Aquarium and Clear Water UL Listed Power Filter 2 Year Manufacturer Warranty The media basket prevents water by pass around the filter media