hey yea dude no prob that why this fourms is here.
the lights sound good, as i posted about the 54 watters that is just what i use which is why i felt i should reccomend them
as far as the roots go, if you have a cooling rack (such used when baking a cake
) then i suggest that you place your rockwool cubes on that and adjust the light accordingly from what i can put together it sounds like you might be over watering? how often do you flood trhe cubes? i would suggest once ever 3-5 days.
and with the b1 you are dead on. b1 is a nute that helps with root growth and early veg it comes in a concentrated form that ou mix with water and put in a spray bottle.
what i think (am im almost 100% sure) is happening is that your over watering the cubes at such a young age, by placing the cubes in the DWC system you are allowing the cube to constantly absorb water there in causing your over watering. so as i said you should see if you can get a cooling rack and let them grow for id say 5 more days on that until u roots that are about 1/8 of an inch away from the bottom of the cube allowing you to se the water level at the tip of the roots rather then the bottom of the cube, remember once your roots tap the water they will grow towards it