Love gettin called into a thread, means folks are payin attention
That said I'm not on here as much as I used to be since I've retired to da farm
Tis true that a sulfur rich medium is good for our plants but elemental sulfur is not the way to go as it is not readily available to the plant and sulfates are !!!
gypsum is not the best option in most cases as it is Calcium Sulfate and too much Cal can cause nute burns and lockouts. Plus let's not forget there is a necessary ratio between Cal & Mag and in most cases there is enough Cal in the water for the plants needs. That is unless you are usin RO or distilled water, then ya need to add it
Most all trace elements are available as sulfates, I use
Magnesium Sulfate
Potassium Sulfate
Copper Sulfate
Zinc Sulfate
Iron Sulfate
Manganese Sulfate
as well as a few others
The important thing to remember is that the ratio's of the elements with respect to N is very critical !!!
Folks need to know how these elements affect things as well. While N is a must for plants it also inhibits THC production while Manganese feeds THC production and iron feeds CBD production
These things are also affected by the spectrum of light, if growing outdoors, no problem as the sun is full spectrum. But if your under HPS lights you will not see much difference as HPS has very little blue and the blue spectrum enhances what sulfates offer the plant
I explain this in great detail in my books