So I need to add some calcium chloride. I'm at 200 the calc says I should be at 250 - 300. Is Ice melt the same thing? 50lb bag of Prestone ice melt at Lowes is $20.
Use it or buy it from the pool store at $25 for 10lb?
People here commonly use road de-icer which is the same stuff. The risk is impurities that can leave stains on a plaster pool. If you use the search function, you should be able to find which brands people here trust. Try "ice melt" "de-icer" etc. and I'm betting you'll find some good information. It's probably fine, but worth the time to check it out here first.
Another option is to use calcium hypochlorite (cal-hypo) as your chlorine source for a while, which causes calcium to rise over time. Safety caution: do not put cal-hypo pucks in the inline chlorinator at the same time as trichlor pucks. The two together can cause explosion and nasty gases.