This works great for me. I’m usually mixing 50-60 gallons at a time. Tells me how many pounds of salt to use. Guess you could also do it by volume of salt.I just dump 1/2 cup per gallon but dont really care of its level...finish up...wait for temp and check salinity and add rodi or more salt if I need
Direct Salt Addition Calculator
Aquarium calculator; Estimate the amount of solid salt required to raise salinity to a target level.
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