Also filling your barrels with a hose do yourself a favor and buy a food grade hose. You can find them in most RV suppliers and even in the auto department at ‘wally world’.
Just for the record, I’m not suggesting your hi-tech prepper with all the latest anti-zombie gear should use old milk jugs, but they are fine for appartment dwellers and others concerned about temporary water outages. Not directed at you kart personally, just sayin.
Marine supply also