I do not use KoolBloom personally but I know two growers (and probably ALOT) who do so I will ask them to stop by this thread and tell you what they think of it. I believe its a bloom booster.....correct? If so then it's more like another product I use called Hydroplex
Hydroplex Bloom Enchancer from 4 hydroponics.com by Growco Indoor Garden Supply

and you start adding that about the fourth week to improve yield. I tend to like to stick to "product lines" (in this case...botanicare) because I think it causes less issues with different nutes etc interacting BUT alot of people use several different brands and do just fine so I'm not saying one is better than the other.

Lk....in sort of sloppy terms I'd probably call it something like a vitamin for your plants or something. I know the Sweet adds carbs but don't ask me to break those two down and tell you how they work. No clue. :stoned: They were recommended to me by the man at my hydro store and his word is law in my book so I use them. How's that for some plant knowledge?