Nute Burn or Deficiencies?

[Meligrow]

First Grow! Inspired to get my feet wet and invest in a tent recently after my neighbor had given me an unknown sativa/sativa dom seedling he'd be growing in front of his window. As I've been slowly acquiring all of the required gear, she initially had nutrient issues and her lower leaves turned yellow and died from the basic potting soil mix she was given in. She was then replanted into a 5L fabric pot on week 2 of veg in a 50/50 mix of foxfarm happy frog. Fast Forward to Week 6.

What Strain is it? Unknown Sativa
Is it in Vegetative or Flowering Stage? Week 4 Veg
If Soil... What is in your Mix? 50/50 Mix Happy Frog/Ocean Forest
If Soil... What Size Pot? 5 Gallons
Size (Wattage) of Light? How Many? Meizhi Reflector-Series 450W @14Inches above canopy
Is it Air Cooled? Yes
Temperature of Room/Cabinet? 68-82F
RH of Room/Cabinet? 40-50% (have since amended since photos)
PH of Medium or Reservoir? 6.9
How Often are you Watering? When Dry (2-3days)
Type and Strength of Fertilizers used? General Hydroponics (For 2L Water) 3/4 tsp FloraGro, 1/2 tsp FloraMicro, 1/4 tsp FloraBloom
Size or Square Footage of Room? 3x2

Should I be changing up my feeding regiment or flushing?
Also any tips on training would also be greatly appreciated

 

[fanleaf]

PH is high. 6.2-6.8 is a good range for soil. Drop down to 6.4 for a while. It may not sound like a big difference however the difference between 6.9 and 6.4 is that 6.4 is 5 times more acidic then 6.9. Dropping down to 6.4 will allow the nutrients to be absorbed by the plant that it cannot uptake at 6.9.

 

[PoppaEvil]

Looks like a deficiency to me. You have a few spots ya see that? If PH is high the likelihood it is getting all it needs is slim; therefore, nutrient burn would be less likely to me. If you aren't into Sulphur to drop PH, can use some alfalfa meal in its place. This is an often made mistake, (not saying you did this) buy the soil that google says in its result, "Best organic soil for cannabis" all the while never knowing the ph of the soil, but only thinking ph of the water that will be used to grow the darlings.

Internet searching is a good base, but coming hear and asking for advice from those not seeking a profit is better imo.

I'm sure you have seen some pictorial guides but I'll attach it as it is still relevant.