first off man to be honest with you i hate rockwool, but thats just me, you know.i kinda saw your growing system and i see that you are using clay around your cube of rockwool. well with that being said this is how i would start my clones.first off after i make my first cut i take my blade and "LIGHTLY" scrape the top layer of the skin off of about half the length that will be going uderground, what this does is give a little bit more surface area for root growth rather than just at the cut site. remember to just scrape it lightly enough to remove just a little bit of skin. now remember that everything that is cut has to heal. i say that because i noticed that you said you cut off two or so nodes, well those cut sites have to heal before any kind of roots get started. what i do is try to cut it with a long enough stem so i don't have any extra cuts(besides the initial cut from the stem), and after it starts showing growth, maybe two weeks, then i might cut off a few of the bottom nudes, i try to let if have a chance to be able to heal itself "after" some roots have formed rather than while the roots are trying to get strarted.now if i just can't help having to cut those nodes so i'll have enough stem to put in, i just make sure that any other cuts are underground, for example it has been times that my first nodes was sitting right above the ground or top of the rockwool cube, and when it grew for a couple of weeks then i cut the last few nodes.but as i said i hate rockwool, so what i would try is a perilite/vermiculate mix in like some plastic dixie cups, and a moisture meter. in my opinion what this does is; first off give your clones a more oxygen rich environment to grow in, plus more room. but you do have to keep somewhat of an eye on it, so use your meter to keep check of the moisture level towards the bottom of the cup. because with the mix being kinda light in texture it may dry out quick, and the meter is better than trying to eyeball it.now me , i like to wait about two or three weeks and after i see one or two good looking nodes have grown out(let's me know roots have formed a little), then i GENTLY remove it from the cup, and GENTLY remove as much of the medium from my roots, and then GENTLY place it in my clay pellets(that have been cleaned), and stack them up enough to support the stem.

ok, fuck that was long. now the other thing i noticed you said is about the distance from the light, if you are using flourescent lights i say get them as close as you possibly can. the light is their food in so many ways, meaning that they need it to grow( or veg)plus the closer the light is, the less stretching it will do, therefore more energy can be used to produce roots, instead of having to stretch to reach the light.and one thing before i go before i started buying seeds or any thing like that i had a whole lot of practice runs with simple bagseeds from the weed that i had bought, you know a dime sack here and a dime sack there. i'd just rather have practiced with some shit that i didn't have to order for 40,50, or 60 bucks for 5 to 10 seeds, you know what i mean?

Hope that helped, sorry that shit was so long,

PEACE!!!!
-ZEN-