I've been using dry nutes for 3 years now.
Tried the original MegaCrop-so so...
I've been running Jacks 3-2-1 for a couple of seasons in everything-hydro, soil and coco grows with very good results.
Simple 3-part: 5-12-26 base mix, Epsom salt(MgSO4), and 15.5-0-0 (Ca(NO3)2).
I also add Tribus bennies and this year I decided to try some silica additive to see if that helps with floppy stems.
Based on the pheno hunt I'm running on 5 Morning Dew girls downstairs in coco and my mono-crop of a killer pheno of Primal Punch upstairs in my 'rdwc room, the Power Si I added made quite a difference in their ability to hold up big colas.