Just a couple of small flourescents is okay. Clones don't need much light at all, in fact too much is a bad thing at this stage. As far as rooting clones in rockwool, it can be tricky, especially for the first timer. I failed with rockwool and it was because I let my cubes get too wet. You want the barely DAMP, but not saturated or heavy at all. If they are saturated they most likely will not dry out before the clones dye. Be careful with the humidity dome as well, if the clones stay too damp they will get slimy and start rotting before they ever root.
I built an aerocloner out of a rubbermaid box, it cost about 35 bucks all together and I have had EVERY clone root. And it only needs plain tap water, no rooting hormone, superthrive, nutes or anything. I would highly recomend building one.
). 1/4" shouldn't be too large to prevent humidity but just large enough to allow for proper air ventilation....your babies NEED air 
