Waterco Multicyclone 200378 75 SqFt MC12 Plus Cartridge Filter with 1.5" Union 50 psi. MultiCyclone Ultra combines centrifugal and cartridge filtration into one streamline housing, creating an ultracompact filtration system that can be vertically installed on a pool pump. It combines the benefits of pre-filtration and a compact cartridge filter enabling a reduction in equipment footprint and required pipe work, reducing the filtration system overall head loss.