Admirals pool store sells a 50 lb bag of sodium bicarbonate for 49 bucks on it it says "industrial" doesn't say the contents or ingrediants but have useage for pool volumes on the back. made from SOLVAY .. this is pretty much what the previous owners used in the pool does anyone know what this stuff contains? (asking for future reference when someone says not to put baking soda in my pool .. I've already bought 108 lbs of AH baking soda for 48 bucks)