Refusing refund for faulty products

I recently bought 8 Bluechem pool floaters when they were on special, and I now believe they were reduced to get rid of the stock because they are faulty. My pool was crystal clear and sparkling blue when I put these floaters in, and within 48hrs my pool had turned green. At first, I blamed the weather, but soon realized it was the floaters. You can hold them right against your nose and not even smell any chlorine. Other floaters smell like chlorine from meters away! The chemicals used to make these are obviously either generally inferior or from a bad batch. This was proven when I put new floaters of a different brand in my pool and it started turning blue again by the next day. I then took those floaters out and left only the Bluechem ones in, and once again, my pool turned green. Now I am stuck with 6 unopened useless pool floaters because Builder's Warehouse is refusing to provide a refund or to replace them with a proper brand, and this company, Bluechem, doesn't seem to truly exist. There is no sign of it anywhere on the internet, the website URL printed on the floaters does not exist (the entire website is nonexistent!), and they are completely uncontactable. There is something very suspicious going on with this brand and Builder's Warehouse is refusing to accept accountability for selling these ***** products from a company that seems to be a facade.