HydroPonic Nutrient Change

How I mix my hydro nutrients and do a nutrient solution change for my Hydroponic tomatoes in the greenhouse.
I got the Master Blend from Morgan County Seeds
https://www.morgancountyseeds.com/pro...
I used 10 grams per 5 gallons, which is 2 grams per gallon.
Morgan County suggest 12 grams per 5 gallons, which is 2.4 grams per gallon, of Master Blend and Calcium Nitrate, and 6 grams per 5 gallons of Epsom Salt.
So an example calculation should looks like this:
Reservoir size: 30 gallons
Master Blend- 30 gallons x 2.4 grams = 72 grams
Calcium Nitrate- 30 gal x 2.4 grams = 72 grams
Epsom Salt - 30 gal x 1.2 grams = 36 grams