I have a new 18000 gal. IG pool/spa combo. I had a Sta-Rite 2 speed pump put in, it's 1 1/2 HP in high and 1/4 HP in low. I am trying to figure out the best run times to make use of the cost savings. The installer told me that normally for a regular pump and my size pool that 8 hours a day, split up over two four hour periods, was sufficient. What I decided on, for now until I know better, was two 6 hour periods, and each of those periods is split in half between high speed and low speed operation. Basically I traded 4 hours of high speed operation for 8 hours of low speed operation. I'm wondering if that really saves me a lot of money and if I am getting the same amount of filtration. Sound right? Any suggestions? The water looks great, btw. I was even tempted to decrease high speed times even further, but the pool cleaner does not work in low speed, so I'm not sure that's a good idea.