Certified Pool Operator Practice Test 2025 – Comprehensive Exam Prep

A cartridge filter is the most effective choice for removing smaller micron particles compared to the other options. Cartridge filters have a porous material that can capture particles as small as 10 microns, while diatomaceous earth can only filter particles between 2-5 microns and high rate sand filters can only filter particles between 20-40 microns. Sump filters, on the other hand, are typically used for mechanical filtration and may not be as effective in removing particles as a cartridge filter.