As an owner of two 6105 and an Apex conntroller, I would suggest that you research your control options for this pump.
After I got mine installed and programmed, I learned that when pulsing this pump the level should never drop below 25%. There is a manufacturers note on this subject. Had I known this I would have made different choices.
As soon as these pumps die I will probably be doing Ecotechs, which allow you to go anywhere from 0 to 100%.