Go to Lowes or where-ever and get the EXACT product name, and company name off the product you're considering. Call their customer support people, and ask them.
One of the dirty little secrets of many construction and pool products is that companies don't change product names every time they change formulation. As a result, what worked before (or for a friend 5 years ago) will not necessarily work now. Only the company will have that information. They may not tell you, but they are the only ones who know for sure.
I'm working on a project to ID all pool chemicals by actual contents, but that's never going to be possible or practical with products like paints, sealants or caulks.
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