If you do the calculations it comes in at around 0.006g/L to remove Chlorine at the rates typically found in municipal water, actually that’s a slight excess to what is needed (mostly).
So to treat say 50l you would need 50*0.006 = 0.3g
A level teaspoon (5mL) is usually regarded as being 7g
Sounds like some people are overdosing slightly, not that it will matter much unless you get really carried away. There are some issues the way some Lager yeasts metabolise Sulphur and there can be flavour/aroma effects if there is too much free sulphur available.
If you are adding it the night before or if the water is warm (and given a few minutes before mashing in) it should be very effective and any excess should gas off pretty quickly.
Mark
So to treat say 50l you would need 50*0.006 = 0.3g
A level teaspoon (5mL) is usually regarded as being 7g
Sounds like some people are overdosing slightly, not that it will matter much unless you get really carried away. There are some issues the way some Lager yeasts metabolise Sulphur and there can be flavour/aroma effects if there is too much free sulphur available.
If you are adding it the night before or if the water is warm (and given a few minutes before mashing in) it should be very effective and any excess should gas off pretty quickly.
Mark