Urgent: Everything is dying :(

[torvald]

Hi my Name is Torvald and i am from Norway
I have a hydroponic nft system running and all plants are showing signs of a magnesium deficiency.

This was a high school project that i brought with me and wanted to continue in private.
While in high school the lettuce never showed any sign of this now with tomatoes and paprika it is literally everywhere.

i believe to know that it is because of the tap water with a 17-1 calcium to magnesium ratio and wanted to replace it with clean rain water and use calcium nitrate and epsomite to cheap out out CalMag a product from the US that has the perfect ratio of 3-to-1.

Would anyone be willing to help me to find out how to mix both ingredients for it to have a 3-1 ratio?
I will use reverse osmosis water or rain water and this a the data i could find for both ingredients:

Calcium Nitrate

15.5 % Nitrate
26,3 % CaO


Epsomite

16 % MgO water-soluble magnesium oxide
32.5 % SO3 water-soluble sulphur trioxide


Tools i have: PH & EC Meter + micro scales

[oz93666]

If you have reverse osmosis , the problem is solved !

I would keep things very simple , use an all purpose chemical fertilizer with trace elements, from a garden centre .... nutrient formulae don't have to be precisely tailored to a specific plant ,the plant just won't eat what it doesn't want ...commercial greenhouses taylor nutrients because they don't want to waste fertilizer ... on a small scale this doesn't matter ..

This and the right Ph cannot fail.