You have to be careful with chemicals from the pool store. They often try and sell you things you don't need and some of those things have stuff in them that cause problems for your water. It would be a good idea for you to do a lot of reading here on the forum, especially the stickies at the tops of the different sections of the forum. Also, do some reading on our sister website www.poolsolutions.com. Lots of good information there as well.
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