I recently installed a 5600SXT control unit (ask me how great Sharkbite stuff is!). The programming went fine except that all online recommendations for the BD (brine draw) setting said to leave at the 60 minute default. It takes about 12 minutes to suck out about 5 gal so that would leave the unit sucking air for 48 minutes. Anyway, I forced a regeneration and indeed that's what happened (air suck) so I jumped to the next step, RR (rapid rinse) and all went OK after that. The BF (brine fill) setting is recommended between 4 and 12 minutes so a 60 minute BD will always get an air suck. Sounds wrong to me. What am I missing? Also, the entire forced regeneration took less than an hour. Is that what to expect? Is the regular (metered) regeneration the same length? I would have expected all this to be longer based on the experience with my old softener.