Additives are not plant food. Don't fall for them, there is no science behind any claims. At best you're feeding the microbes in the soil, but with what, and how is that improving plant health?
Those products are loaded with preservatives; they couldn't exists without them. Methyl paraben, sodium benzoate and others including ascorbic acid. Ascorbate isn't bad on it's own, but combined with sodium benzoate it makes benzene.
http://naturallysavvy.com/eat/this-is-why-sodium-benzoate-is-so-scary
If you mix the product full of ascorbate with the one that's chok full of sodium benzoate in your reservoir, then you're making benzene. Those manufacturers know this too, and they don't report it on their labels. I know this because I worked for them.
Some products have both ascorbate and sodium benzoate in them already, plus parabens. These are bottled preservatives, before they are anything else.
When manufacturing those additives, the first ingredients mixed-in are the preservatives; it starts with a 10,000 liter tank of hot water and kilos of parabens and chemical preservatives go in first. The parabens are waxes, so they take alot of mixing in, and then the "food" ingredients are added after. I have stood there and watched it happen while I was employed at a "cannabis" fertilizer manufacturer, like the ones you mention.
The preservatives are used in huge amounts, way more than in any human food product, because those bottles of crap wouldn't stay stable on shelves for months on end without them. Plus there are dyes and perfumes added ! If anyone tested those additives for the amounts of preservatives found in those bottles, it'll be in the full percentages, just like an N-P-K rating.
B52 has urea in it, that's why is "works", but along with the preservatives it's not listed on the label . Urea is a super good source of NH4 nitrogen and any crop will green up in a day if you provide it with urea. But urea is not mentioned on B52's label.
If you really want to add sugar to your plants' soil, just go buy some. Why buy carbo load? Same with the vitamins - go buy a B-complex pill and add that to your res'. If you want to add anything that's claimed to be in those additives, you can simply buy it pure from somewhere else. I would throw those free samples of preservatives out, or take them back to the store.
No self respecting farmer or agriculturist would ever use any such nonsense products on their crops, so why are cannabis growers so gullible ? We must educate ourselves and share the facts of horticuture; this manufacturer-driven hype is as bad as fake-news!
