Vacuum Cartridge filtration allows for much higher quality filtration at extremely slow filter speeds. We use a nominal 20 Micron cartridge with a maximum of 0.25gpm/sqft of filter area. This yields a 20 to 5 micron range with extended filter runs between cleanings. This system wastes the least amount of chemically treated water and is the most simple to clean. With an extra cartridge set the entire system can go from 100% fouled to 100% operational in less than 5 minutes.