So the pot u have em in right now is just their starter salad, wanna give em some meat and potatoes on the up pot then check out this recipe and treat ur promix like 100% peat in the 25% u would use , couple bags of compost which sounds like u also already have, bag of perlite and sounds like ur already using Dr earth and have that on hand 
You def in the right direction and this mix I’ve had nothing but excellent results, I also tickle my soil with microbes doing compost tea feedings that I’m also happy to share the recipes I like to use as a backbone if u feel like going down that rabbit hole too