3/4 tsp per gallon is what my package says. Don't know what that would be in grams, my scale isn't accurate at low quantities.
Remember one unassailable statistic, as explained by the late, great George Carlin: "Just think of how stupid the average person is, and then realize half of them are even stupider!"
"I would like to die on Mars, just not on impact." Elon Musk