All summer my CH has been around 350 or so. All of a sudden it jumps to between 465 and 496. Consistent like this for a few weeks. Nothing has really changed, except the water temps have dropped with the cooler weather. Based on my other numbers it is still balanced, but when it warms up again it will be hard to keep it balanced. I am planning to run the pool all winter as it has a spa. Should I just wait and see how it does over the winter or try and get the CH down now? I am on a well, and if I use the water that comes from the filter it is close to 0 in CH. What would cause a jump in CH? I havent added anything. Thanks.