I've done a lot of coco grows and usually veg at around 450ppm and flower at 900ppm 500scale. pH 5.8veg/6.3flower
To me it looks a lil overfed and has some pH issues
Lower your ppm and pH to 5.8 until the leaves straighten out.
I'd go for two 1000w fixtures if you can handle the heat and have enough head room.
6x6 = 36
2000w / 36 = 55.55555555555556 wpsf
1000w is the choice for serious growers because the penetration outperforms the others.