I'm building a cabinet for my very first grow, and have settled on Master Blend (their 4-18-38 Tomato formula, plus Calcium Nitrate (15.5-0-0) in equal parts, and Epsom Salts (half as much), very similar to Jack's. Real cheap, and goes a LONG way, and as I understand it, needs no additional amendments throughout the grow cycle, controlling only for pH and EC. You can make up concentrates if you want, and then dial up whatever EC you need by controlling the concentrate/water mix.
I want my cabinet to be as automated, and as stupid-proof as I can make it. Hope to control the heat and humidity with Inkbird controllers, in a way that uses the vent fan as little as possible, while keeping VPD where it should be, and using CO2 bags to get more growth from my LED lights. I'm surprised at how few people favor this approach, preferring instead to buy or build exotic soil mixes, then adding all kinds of amendments. So far, I've bought just about all the parts I'll need, and am about to start putting it together, hope to create a post to document it all. Hope growing the stuff is as much fun as designing the cabinet has been!!
