Organic nutes and coco are not a good match. Organic nutes do better feeding the soil flora than they do at feeding plants. Coco is a hydroponic medium, if you want to stick with it, you are better sticking with hydroponic nutes. Megacrop is cheap and effective.
If you want to go organic, I suggest larger pots and well "cooked" soil. If you go for soil in autopots, I suggest that the bottom couple inches be at least 50% perlite to make sure that the flood zone aerates well between the flood cycles. Unless you go with pots more than at least 7 or so gallons, you will need to supplement, and again, organic nutes may not do the job because they are slow to become available. If I combine the soil I have been cooking this summer with the autopot system, I will likely use 10 gallon fabric pots irrigated in my own tray by autovalves, and I will have Megacrop ready if needed.
There is lots of information on here about either coco or soil/organics, but you are best sticking with one or the other, not trying to combine the two. If you dig around here, you will find that many attempts to combine coco/perlite with organic nutes run into problems. The good news is that with coco, you can always flush and start over with hydroponic nutes, if of course, you have any available when you need them. With soil, if you run into problems they can be tougher to sort out because knowing exactly what the problem is and figuring how to fix it without generating other issues can be hard.
Good luck with your decision and your grow.