I'm actually using four speeds. But then my pool has a SWG, in floor cleaning system, and solar heating. Each task may require a different speed. You always look for the lowest effective speed for each task. I run a short cleaning cycle in the AM at 2800rpm, skim and chlorinating at 1400rpm mid day, and 1000rpm for extra filtration late afternoon. Anytime heat is called for and available, the solar controller ramps the pump up to 2600 and opens the valves to the solar panels.