I use a locally manufactured version;
Hydro-gardens.com
https://hydro-gardens.com/product/hydroponic-special-formula-25lbs-bag-5-11-26/
- 5-11-26 hydroponic special mix
- Calcium nitrate (Yara brand)
- Mag sulfate, aka epsom salt
- MKP, aka monopotassium phosphate (Haifa Brand)
I checked the numbers and this stuff has higher levels of micros.
Also, using the above mentioned brands I was able to save substantially over the equivalent Jacks products.
These nutrients are what commercial greenhouses use, as well as many commercial Cannabis facilities here in Colorado.
Whether or not you want to supplement with epsom salt or MKP, these dry nutrient salts give the grower complete control over their plant nutrition, because you know exactly what's in them.
They give you one more thing as well; peace of mind, because you know what ISN'T in them. No strange additives, no preservatives, no emulsifiers, no PGRs, just the salts.
They're a perfect foundation for any nutrient profile you might want. There's no reason not to add humic and fulvic acids, for example. Not that there's any particular need to do so.