I am a beginner as well but I would recommend using organic nutrients (i use
bio bizz) they are natural so you will experience much less trouble with nute burn and salt build up in the root system. I have had 0 issues with it and from what I have read it results in a much smoother and flavorful buds.
www.biobizz.com
Also, getting a cheap pH testing kit for your water and a digital thermometer. You want the water at 22°c (this is the optimum temp for plants to absorb nutrients) and PH around 6.2 - 6.8. This is really beneficial to the plant and cheap to implement.
See if you can find a larger fabric pot and repot it with quality soil (providing it is still in Vegetative state. The fabric pots naturally control the riot system and eliminate the problem of root balling. When the roots are exposed to oxygen at the sides of the pot they naturally die off as opposed to curling round and round and potentially suffocating in a plastic one.
Finally, if that is a LED I would put it closer to the plant so it doesn't stretch too much and will get a stronger intensity of light.
Hope this helps somewhat, good luck dude. ✌