leaf tip turning white light or nute burn

[growsince79]

my plants will be 6 weeks old tomorrow i got 1 mars hydro tsl2000 and 2 mars hydro ts1000 there about 20 inchs from the top of the plants i turned the lights up to 80 percent last night
i have only feed with nutes 2 times at 1/4 strength and have watered between feedings
on 9/4 i watered 5 gallon mix divided by 8 plants
big bloom 3.5 tsp p.h. 6.3
grow big 3.5 tsp ppm 299
cal mag 2 tsp
on 9/4 i watered with plain water
im using pro mix moisture potting mix View attachment 1167683View attachment 1167684

I'd quit the big bloom and double grow big to 600ppm.

 

[biggerbud420]

I'd quit the big bloom and double grow big to 600ppm.

i had already planned to go from 1/4 strenght to half strenght on my next feeding