Test your FILL water (pH, TA, CH only) and post those results. I can then calculate doses -- once your pool is full -- to bring you into a safe range for winter.

If you have had problems in previous years with the pool being slimy on opening you may want to consider the additional steps of raising borates (> 60 ppm) and lowering phosphates (< 0.125 ppm) prior to closing. Alternatively, you can maintain intermittent chlorination while closed. I can help you pursue either or both.