Thanks Jim, I think I see what you mean. Can you confirm?
Can I just follow the first step here:
Dissolve 1 gram in 100o mL (grams) fresh water. Manganese = 280 ppm.
Then to target 0.88 ug/L in 350 US gallons, use 4.16 mL?
My numbers agree with @JimWelsh 's recommendation.
350 gallons = 1325 L
280 ppm = 280,000 ug/L
0.88 ug/L * 1325 L = 1166 ug
1166 ug / ( 280,000 ug/L) = .00416 L = 4.16 mL
