Hmmmmmm, let's see......what have I heard about Canna? A little bit of personal history is in order. I and a few others (potroast for one) have been posting about growing pot for well over a decade, before high tech internet and modern websites were around. First there was ADPC, a newsgroup, and then a real forum came along called marihemp aka cannabis.com designed by a fella by the name of Ron.
It was a site where all the heavy weights in this new industry congregated - Vic High, Brothers Grimm, Sensi, Greenman, me, Newbie aka Lucas, etc. Lot's of chatter, some noise but it worked....for a while. I modded 7 forums by myself. There were only a handful of seedbanks back then. One of the first Dutch pot companies to post to cannabis.com was Canna, and they were hawking a product that I found most disgusting, harmful. Was probably the start of what I suspected was the future direction for this biz. But I digress.....Canna's main spokesman (the owner) and I went toe to toe in threads regarding C02 tabs he offered which were supposed to do things for pot that would make you go bonkers.....all the typical flowery fluff, claims, and bullshit. Problem? C02 gas happens to be toxic to any plant's root system. Didn't matter what botanical thought I presented, he was going to say the sky was mauve and you better believe it's true. So, here he is pimping these high priced worthless tablets, noobs are eating it up (as dreamy noobs do) not giving a shit about the community and ignoring common sense botany.
I was using coir 30 years ago with orchids before it became fashionable in lala land.
There's another problem with most if not all "cannabis specific" nute ratios - they are too damn high in K compared with N. I really don't think any of them know or care about plant nutrition as some of this stuff is just way over the top regarding its design..... and of course they design in the need for additives and boosters by making their "base" products deficient in the first place. It's a racket.
This is a concept you need to learn well, nutrient antagonism -->
http://www.totalgro.com/concepts.htm
An overage of K will impede the uptake of 3 of the most important elements for good cannabis nutrition - N, Ca, Mg.
UB