New answers tagged campden
AFAIK, the tabs are standardized. One tab has enough sulfite to treat 20 gal. of water, so 1/2 tab is enough for your needs. If the tabs are are 550 mg., I'd base the powder measurements on that. It would be easy to add a dose of powder and either smell or taste the water to see how effective it was. BTW, water guru Martin Brungard has recently written ...
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