Sodium Metabisulphite 500 g
A big tub of Sodium Metabisulphite. It's in a resealable tub.
WE don't use metabisulphite anymore. We prefer the other sterilisers. It gives off very unpleasant fumes and can trigger asthma attacks. The only advantage is that you don't have to rinse it off. If your water is unhealthy you don't want to use it for rinsing but water in the UK is so good it's not an issue.