Call Sears and have them verify the rated capacity of your softener against your waters present hardness. If your brine tank is still empty place the softener control head in the brine draw position use a flashlight to check the sides of the brine tank. The liquid level should be slowly dropping (hard to see watch surface tension of water against side of brine tank). I would also like to know if this is well water or city water and your TDS level (total dissolved solids).
Respectfully David F. Walling