My first grow (Royal Dwarf)

Your plants are fine brother ! They aren't suffering from anything . The main thing you wanna focus on when they are young like that is not over watering them . Your starting PH in a soiless mix in my opinion should be 6.1 6.2 and you would gradually move it up to 6.3 or 6.4 this will ensure that your plant will not suffer from nutrient lock outs . I can see that you are folliar spraying your plants although this is good for them I wouldn't do it every day I would do it every 3 days or so , reason being is that when they are young like that a lot of what they absorb is through the leaves , so do it sparingly when young like that so you avoid over watering issues . As they get a little bit older you can add a rooting stimulate like piranha or voodoo juice (anything like those products is fine don't have to be those ones) a chelation agent ( humic / fulvic acids) and very very very light dose of which ever Veg solution you have chosen . If you do these things you will have no problems in the veg cycle and you will have wonderful healthy plants . I hope I've helped a little bit :)

Height is over rated. What you want is an even canopy; that been said, the stretch will pick up its pace during the 2nd week of flowering. Now lights, your grow space is 60*60 (4 sq ft) for LED lights, you need between 30 to 40 watts per sq ft, in this case 150 watts puts you at 37.5 watts / sq ft, so I don't recommend more light, but if you can get away with it, get the lights closer, that will certainly help the plant, as long as the temperature at canopy level is appropriate; keep in mind that getting the light closer increases the intensity of light dramatically for the plant. Since you are using a soiless media, I would add some form of cal / mag additive, just enough to get 0.5 EC (250 PPM) as a base water (0.5 to 1 cc per liter should do, depending on your water EC/PPM). Also up the biogrow to 2 cc/lt and start adding bio-bloom as soon as you see the first flowers (2 cc / lt should do for starters).

Hello ! At that stage in soilless medium you should already be around 1.5 / 1.7 Ec and the cal mag should represents 0.3 points of Ec which mean that with a tap water at 0.3 Ec you add cal mag until 0.6 is reached then you go to 1.5/1.7 by mixing your nutrients. So to answer your question : yes you need to add more nuts. And you can't do anything to make her gain more height as the stretch is now almost done so until harvest the gain of height will not be up to 5cm. I hope it will help you 😁👍