The product missed its original purpose, namely to prevent algae growth and kill with shock treatment. I collected my pool and diverse experiences for 20 years. For example, the pH value is very important, therefore it is checked several times a week. Such a bad algae such as this, I had never, even after the shock treatment (400 ml per 10 cubic meters of water), the algae grow merrily on (always, of course, pH 7.2, disinfectant Oxy3-pro) I have in 3 weeks after refilling consumed most of the canister and my pool is green Nevertheless, if I had nothing reingemacht saw it not worse.