Absolutely 
Infact, wuth the GH trio you dont even need the cal-mag most often.
The brown bottle is 5% calcium.
Magnesium is not kinda low so it’s good to have some on hand incase Magnesium deficiency pops up.
But I use GH exclusively. Ive used aot of the trio and lately i been useing GH 1 part Maxi series.
I use a little cal-mag sometimes but no other addictives at all.
Here my current grow useing just GH Maxi-gro fir veg and Maxi-bloom for bloom, h2o2, and a little cal-mag sometimes.
Theres past grow journals under my profile if you want to see other plants grew with nothing but GH.
As others have said, ph coco-coir at 5.8 is best
Supplements are most often a waist of money, silica is good but not necessary, I would advice a root inoculant like H2O2 or hydrogaurd but its not necessary either really if you water by hand but there is dome good benefits to H2O2 in you nutrient solution