Oh, ok. Thats NOT a 600 watt light. Look at the second line in the specs. Its actually a 108 watt light, which is on the weak side. That 600 watt number is pure 100% BS marketing crap.
If anything, you could probably move the light a lot closer and be just fine. The leaves will tell you if you are too close. You will get light burn and curling.
For a rough guide to get you started - put you hand at canopy level with the lights ON. If you can hold it there comfortably, the light is fine. If your hand gets too hot, the leaves will also think its too hot, and that means its too close.
Every thing else looks ok to me other than the fact you have no idea about PH or EC. EC is one way to measure strength of the nutes by the way. PH is more forgiving in soil, but its still important. I would suggest you look into a PH meter of some sort or even test drops would be get you close. Just dont get one of those cheap $10-$15 ph pens. They are worse than useless because they are never accurate.
With something like Fox Farm, measuring EC is less important as long as you measure carefully, but a way to measure EC accurately would be best.
How strong are you mixing your Fox Farm? The leaves look a little dark, but there isnt much sign of nute burn, so Im guessing your in the ball park. I would recomend you stay at 1/4 to no more than 1/2 the strength listed on the bottles.
There is maybe some discoloration around the tips, but its hard to judge from those pics. You could have a nute imbalance from an incorrect PH or you could just be over watering at this point - hard to say.
Those look like fabric pots? Are the elevated in some way so they dont sit in standing water? You want the soil to dry out pretty well between watering. You mixed in perlite, which is a good thing.
I would not water until the pots start to feel light. You can also check the stems. if they are getting soft and flexible, they need water. If they are stiff and firm, they dont. Over watering is just as bad as under watering.
Edit: If you think you have been over feeding, then do a flush with plain water every other feeding for a while. That will help clear out built up salts in the soil.
. The will now be getting a lot more for the pot size.
