Calcium nitrate / Epsom salt how much to add

In ro water how much calcium nitrate 15.5-0-0 and Epsom salt should I add per gallon of water in a dwc?

No idea about the calcium but 1 tea spoon of epsom per gallon, thats what i add for coco

1/4 teaspoon per gallon of water for calcium

Wow SV, that is an awful lotsa Mg, ya think!..Even for coco..A tsp~5gr of ES would give you~ 130ppm mg and ~173ppm S, no?..Epsom Salt is 9.8% Mg 13%S
I try and stay close to a 2:1 Ca:Mg ratio or there abouts unless I see a need for more Mg..I usually add anywhere from 1/4gr to 1gr per gal..1gr of ES will give you ~26ppm Mg 34ppm S..
My 2cents..