Soak your hydrometer in vinegar, rinse and then test in tap water. Continue soaking and rinsing until your tap water read 1.000. Without a baseline you have no measurement.
Pufferpunk said:I don't measure with a spoon, I measure with a hydrometer. I keep my GSP at a specific gravity of 1.014-19. That comes out to about 2 cups of marine salt/10 gallons. Teaspoons?????