If your pool is clear, then you can simply maintain a residual Free Chlorine value of 8 to 15ppm for the season, the range for CYA of 100ppm or more.
You'll find you use less chlorine, too---but you MUST keep it in that range. If your CYA is really far beyond 100ppm, stay closer to the 15ppm level. You'll STILL use less chlorine.

Carl