How and why are you adjusting the ph down to 6.0? Especially if you are adding nutes after adjusting. Way too low for soil, but I've never grown in coco. Target ph should be around 6.3 to 6.8.

...And why is your 600w light 1 meter away? (should be within about 1/3 to 1/2 meter, maximum)

What did you change after two weeks, and why?
What are you using to adjust your ph?
What's the runoff ph?