How you don't algae and scaling with those numbers is kind of a miracle.
CH 1000?
CYA 300?
TA 240?
FC 3?
TC 5 ?
(therefore CC=2)

Your FC needs to be AT A MINIMUM 8ppm and you need to shock the pool to 25ppm just to get rid of the CC.

You also need to go through the TA lowering procedure--with your CH at 1000, I suggest you follow Chem_Geek's and Waterbear's usual advice about getting TA down to around 50.

Draining and refilling will help get those out-of-control #s back in control, but not if you are going to continue to use tabs. Right now, the ONLY forms of chlorine you should be using are bleach/Liquid Chlorine. Lithium Chloride would be OK but it's insanely expensive.

Good luck!