Coco is the one thing I have not tried to create a better gas exchange. My perlite/pumice/cactus & succulent soil/sand portion of my mix is up to almost half of the total volume. Yet I still cannot get my soil to drain properly or provide space for root expansion. My root balls are severely stunted making the plants difficult to water and unsteady in the Santa Ana winds even with silica supplementation. I had thought leftover hyphae from mycorrhizae supplementation from previous grows, after being raked in the sun for a week to kill any pathogens that had wiped out my first grow this year. So for my fourth try this season, now with an auto (Bruce Banner Fast) none of the leftover soil was used. I used fresh Ocean Forest and compost with a 40% mix of the above noted "circulation additives" and still have a pot of wet mud that can't breathe. This mix is touted all over as correct, so why doesn't it work for me? My pots are 21" tall!! I also have used a plant stake to poke 30+-holes to the bottom of my tall plastic cans (see pics) for drainage and circulation to no effect. I have now gone thru 56! seeds this year to get a half dozen runted waste of times. I've used the same mixes for previous seasons with fine success, I'm still at a total loss as to why I can't grow this year due to soil problems not draining. Yes, it is a little cooler this year, but not enough to make this much trouble. I cannot repot again as I now have a broken shoulder. I'm going away for a week so plants may die anyway as I have no one to help water. I bought an automatic watering system only to realize it only uses tap water which here is poison to young seedlings with a PPM over 500!! And it's full of chlorine and chloramines. I may try another auto when I return, I'll no doubt have some empty cans by then as the plants die off.Excellent subject. One of the reasons I've gone to using coco in my cloth air pots, I've also started to regulate things like temp, humidity and air movement in the room, much more closely. I've also take many of these steps to eliminate the problems of over/under water.
Do you think that adding amendments to coco, such as possibly some perlite, or even possibly larger pieces like bark, might create some small spaces within the media that could be of benefit of increasing oxygen exchange? Would numerous amounts of tiny empty voids in the medium allow better root proliferation? Or is coco pretty much as optimized as it possibly can be. Or maybe even regulating the media structure from the bottom upwards to the top point, creating a slightly different mixture content in an ascending direction, to help optimize better oxygen transfer in all parts of the media.
There's so much about this subject in particular to explore new and novel ways of increasing/optimizing gas exchange in the media, it's a very critical factor, no doubt.