i like your idea, however, rockwool is very unstable, and i think with usin cyco, as it's a liquid fert, with salts, the salt would be a fuckin issue, and sounds like more trouble, i heard rockwool is very unstable by itself, u say you got perlite around it and all, and you say with the extra pump it continuously recircs? is that what u mean?, hard to picture what u mean, is this a BIG rockwool slab?
yeah a slab that fits into crop box, mate the reality is any medium even perlite is unstable until you add your feed, thats why its called a medium, its only a means to protect roots and give plant stability, other than that the medium you use is irrelevant, its finding the right medium to deal with your strain, feed and cyclic timing of feed that encourages and pushes growth, perlite is good as a medium due to its drainage and retention qualities, it holds quite alot of moisture inc feed, same with coco, it only holds what feed it needs, well, rockwool is no different.
As for the pump, so you understand, think of each bottom pot holding your solution level at the drainage hole, as it spills into next pot, that pot will fill till it gets to the same level as the drainage hole, once that happens it will spill into the next pot as water is being pumped into the first pot, once all pots are full and it spills into the drainage, it runs back to your res, then again the pump pumps it into the bottom of first pot which will have a water level at drainage height. its an overflow effect basically causing a current through all the pots, as water drains more is pumped into the pot to replace, do you see what i mean.
Heres top view ; ( lame pics i know, only to give you idea )
Side view ; ( the pump forces each crop pot to overflow into the next, and eventually back to the res.
Second pump is a small pump to run a 13mm feed line to top, any left over solution from feed drips back into running solution, it doesnt sit stagnant in pot until solution level is at drainage height, a continuous current that also oxygenates the solution.