.....yo, dry out too fast in smart pots if not large enough....
I run in three gallon pots and only because they don't tip over as easy as one gallon. Watering frequency is key with coco(I use blumats) but with my minute of experience in coco, you can do exactly the same in a five gallon as a one gallon......veg being the key for size. Rootbound, lol, yeah and it aint never been an issue!
Learn that Drip Clean is your friend and you don't need any fancy expensive nutes. Haha, and for chemical, Maxi-bloom....maybe a tad of ProTek(silicon) for pH up......
remember, it only takes 2 months to flower(give or take)........building the un-necessary perfect biological medium with all the microbes and colonies of ...? IMHO, is not necessary.....
Just imho, and what I do.....
gman