I'd be surprised if two grams got you to 1.0 EC, I was thinking 3-4 grams (based off some dry salts I have already). Either way, of course dry salts are going to be cheaper but what you're doing there is fairly advanced. Many folks don't have that level of knowledge to know that a mix of a few parts of this with a couple parts of that results in an ideal mineral balance for veg or flower. Heck, many folks can't even dial in an EC that their plants like.
The alternative that I was mentioning earlier uses two parts in equal amounts and would literally cost $6 or $7 more to use in a 15 gallon res run at 1.0 EC over a two month flowering cycle. Sure, that adds up when running multiple reservoirs but how important is it to a grower for a company to take the guesswork out of growing healthy plants? I'm not talking about any 'pH perfect' nonsense, it's just nice to use a couple bottles to target an EC and not have to worry about issues popping up. I may be a DG fanboy but the 'ease of use' of Aqua Flakes really impressed me.
With that being said, I'm curious to try a high K formula in hydro and might see if I can order some of that mix in smaller quantities if available. Or I can just add some of my potassium sulfate to something I already use.
