We haven't used the pool since September but I have kept up on cleaning and making sure levels were good. I didn't do a test for about 2 weeks because I was out of town but last week I did and things were good except the FC which was about 25. I want to close it up this weekend and secure the cover, my question is how high of a FC level is too high, I'm planning on draining half the water and letting the rest freeze.