I used to use the canna coco in the bag and love the shit, but recently I switched to the brick and I got to say I'm really liking this to. I use %100 coco and I don't "charge" my coco (not telling anyone else they shouldn't) just do a good flush wit tap water tell the brown stuff runs clear then hit it with some nutrients and my plants seem to love it. Been using coco for a while now and can't imagine using nothing else
yeah, if you are otherwise uninformed like I was, then read all the sh+t posted by ignoramuses on the net, you tend to get a lil paranoid .....
I started to buy the pre-made stuff at a slight premium $$$ but went ahead and got the cheaper GH 5Kg brick (CocoTek? I dunno) ...did a few plants in str8 coco and a few others in various ratio mixes with perlite....
just my "new-at-this" small-sample-sized- opinion but:
a) I don't think you gotta do much with the more well known commercial brands of coco beyond a fresh water flush or maybe a pre-soak in Cal-mag (I did some of both, noticed no lock-out or issues in either "test subjects")
b) I'm pretty sure now mixing in perlite isn't a absolute mandate, BUT since I got my plants on automatic drippers, it appears those with a 70/30 coco-perlite mix are 100% immune to over watering wilt (obviously)...the trade-off being: the perlite mix plants have more waste/runoff (again; obviously)
c) I'm experimenting to see if Coco specific nutes even matter: looks like it does (tentatively speaking)