After 4 months of tons of Rain, a Leak in My Pool, and a lot of Refill, my CYA went from 133 to 33. It's time for me to start using 3" Chlorine Tabs again. I was told the Tabs Walmart sells for cheap are made in China & you really don't know what the Ingredients & their Percentage are. I want to make sure I buy decent tabs that won't send my CYA through the roof again. What do you guys recommend? Who do you trust? Thanks in advance.