i've used "hydro" nutes in soil with no problems. just make sure to compliment what the soil has... as that depletes you'll need some sort of ramp up schedule and start low in concnetration to start. I did this for about a year re-using some FFOF. Obviously by the 2nd use it was mostly devoid of nutes beside what i provided, which was more like a 'soilless' schedule and fertigation practices (10% runoff religiously)
Take some notes. Observe and adjust. Do better next time.
if you want to use soilless/hydro nutes, just buy a soilless medium next time. Keep it simple.
"coco" nutes means "soiless/hydro" nutes. It's a useless classification to call it "coco nutes". There's nothing special about coco coir than any other common sense soilless substrate option. the fluffier, airy stuff tends to outperform things that will physically impede roots, like large clay balls or huge chunky perlite (like #4 and larger.. #2 is best if i recall).
if processed properly it neither adds nor leaches anything from your nutes. If it does, that is a bad manufacturer and you should avoid that source in future. unrefined coco is very danagerous for your plants. It'll contain a shitload of Na and often leach Calcium from your feed which will displace other cations like Na and K etc. If processed properly, this stuff will be lost and gained in equal amounts (equilibrium) and will not leach any nutes, nor contain any Na. An 'inert' medium is the result.
anyway, soilless/hydro nutes are the way to go if you want faster growth, but if you do keep it simple next time and just get a soilless substrate.