You can use soil, or more specifically 70% soil/30% perlite, which is what I did/am doing with autopots. I use MegaCrop, which is a one part nutrient, combined with Recharge (beneficial microbes you buy on Amazon). The only other additives I use are Drip Clean and pH Up/Down. Start by watering through the pots with weak Recharge the night before planting. Then, after planting, just water the seed/seedlings from the top for the first 2.5-3 weeks, until the leaves' edges reach the edge of the pot, then you can "turn on" the reservoir. For soil, maybe start out at 450 ppm that first fill of 4-5 gallons, then on the next fill, go to 500-525 and leave it there the rest of the grow. Manage to 6.4 pH (for soil). And that's about all they take, management wise. A circulating pump running in the res for 15 min 3-4 times a day is plenty to keep it nice and mixed up. I think what Goud learned is leaving the pump on 24/7 will raise the pH up quickly, but I could be mistaken. The pH will gradually creep up a tenth of a point every few days with the minimal pump schedule, just adjust back down to 6.3 when it gets to 6.7 or so. And don't buy a cheap pH meter!
If you're interested in maximizing returns as well as automating the watering/feeding, get the 5 gallon fabric autopots, and an air pump with the air domes. And get some strong lights and start learning about Vapor Pressure Deficit (VPD). If you're more interested in just automating the watering, autopots in whatever configuration will do great.
The key things to remember with autopots, from my limited experience: never top water once you've started bottom feeding, and keep the PPM under 550 for the reasons Olderfart mentioned above, buy and install your own 1/4" valve between the res and pots so you can turn the system on or off, and supplement the rootzones with Recharge once every week or two by turning off the res and manually bottom feeding the Recharge into each pot. Oh, and ignore the Bud Explosion and other additives for MegaCrop. The new formula is plenty for the duration of the grow, no supplements needed, a lesson I'm just learning today.