As Steve said, I get it at Canadian Tire. Open it outside, suck some into a syringe and inject into thing wanted dead. Works for aptaisia too. If you have a smaller tank, only do a half dozen at a time so you don't affect pH. Don't get it on your skin or in your eyes. Don't ever add water to acid. Opening in the house will cause it to react with humidity and give off gas. Don't open inside
