Once your plants are rocking in your UC the medium used above the water line is not being used like it would in a regular soil grow. Most of your plant food source will be from the stew flowing through your system. When I do coco in my net pots I stack the bottom with stones before the coco. I would imagine if using the
smart pots you would do the same to keep from consistently drenching your soil. Like when i do coco in my UC I would get that plant well rooted in your pot before entering your UC so those roots can feel that water below once put into the UC. That would help from having to top feed too much while starting in the UC. In my experience I have found faster rooting into my modules if I don't have to top feed at all. When I top fed in my UC with coco in my pots the roots stayed in my net pots a lot longer before searching for that water below. Once they did and I dropped the water level and they exploded and it was nice to have a solid medium to crown feed or top feed as I wished... I now run a coco hydroton mix in all my UC buckets but I do pre veg to get them well rooted before I pop them in. Just my thoughts. Please share if you decide to go smarties and soil, I'd like to see...