Bro, more light - faster metabolism, bigger appetite. Yes, they are already a bit hungry for nutes, 11 days is enough for starting real veg
Give em small amount of nutes, jus take your nutes and put 50% of recommended amount to your tank and wait 3 days. After 3 days you will see if your plants like it or not. Cannabis has a hunger for nutes, best way is to keep it just on the top level, slight overdose is also not so bad, especially in hydro. You could add plain water any time to lower ppm, if you see that leaves are too dark / leave tips are burnt or other symptoms of overdosing. One thing is for sure - they will not be happy for a long time with plain water, they need micro elements to build mass
Also could you take photos of roots? Interesting, how many are there and is plant capable of starting to get nutes.