DW,
With a single speed pump, the goal was to run for the shortest time possible, just because of the cost of electricity.
The opposite is true with a VS pump.. You want to run as long as you can, at the slowest speed that gets things done.. Just because of the cost of electricity...
It sounds odd at first, but many of us run our pump 24/7/365, mostly at a low rpm..
This is perfect for a Saltwater pool, as you can make a little chlorine all the time, and skim all the time. I personally like the look of my pool when there is a little motion to the water.
The slowest speed that you ever want to run would be the speed (%) that turns on your SWCG's flow switch plus a little extra, to just make sure..
With a single speed pump, when you looked down into your skimmer, there was a lot of 'action' to the water flow.. When you look down into your skimmer, when you have a VS pump running at a low speed, it will almost look like nothing is happening. So, many new VS owners think it is necessary crank up the speed to get the skimmers to work.. But.. that is not at all necessary.. Your skimmers work due to the way the weir door works, and not the amount of suction from the pump.
Just as a reference... I run my 3 HP IntelliFlo at 1200 rpm most of time.. If I had a heater, I'd have to run at about 1500 to 1800 rpm.. 24/7 costs me less than $20 bucks a month.. and my pump is about 12 years old.. Newer pump are much more energy efficient.
Just some food for thought..
Thanks,
Jim R.