Make a calculation to work out the correct size of pump for your pool. The Solar Power at Home website gives the example of a typical-sized 20,000-gallon pool at five hours' pumping time per day -- 5 hours times 60 minutes equals 300 minutes; 20,000 gallons divided by 300 minutes equals 67 gallons per minute. So the pump is required to move 67 gallons per minute for five hours each day, the website says, in order to filter the pool's entire contents on a daily basis.
Choose which type of filter you want to use in your system. This could be sand, cartridge or diatomaceous earth (a natural substance found in soil).
Decide which setup system you want to pursue. A "stand-alone" solar filtration system sends wattage direct from the sun panels to the pool pump without the need to connect to any other form of electricity. It is possible to power an AC pump with solar energy by converting the direct current through a power inverter, but it will require more watts of solar power to run them than a DC pump will.
Insert a variable-speed pump controller between the solar array and the pump. This enables the solar pump to vary its speed dependent on the availability of sunlight, improving system control and diagnostics while minimizing energy output and overall running costs.