New pool owner here. I've been reading and researching a lot but need some help.
I'm estimating the pool is 20,000 gallon plaster. Pentair CCP Filter. Has a inline chlorinator. Previous owner used PoolBrand tablets.
It has algae forming.
With the TF-100 Test Kit I got the following results:
So I definitely need to add some bleach. Calculator says 121oz of 8.25% to raise to 4 or 241 to shock. 75oz of baking soda to raise TA
My big concern is how did the CH get so high and do I really need to drain half my pool?
Help! What is my best course of action?