Yellowing of new growth after light flip

[Smoklahoma]

Is this normal one day after changing light cycle to 12/12.
Temp is 78 f. Rh is 58% Co2 is 1200 ppm. Rdwc GH flora expert feed schedule at 50%. Two days before this I changed nuts to week 4 transition schedule. Lowered lights a few inches ( trying to find best height) might have got too close. Already raised light back to 20 inches. Fixing to go see what they look like this morning.

 

[Smoklahoma]

Res. Ph is 5.8 lowered to 5.5 every 12 hrs. Ppm is 710, 280 is straight water. Temp is 64 deg f.

 

[YYCannabis]

I think the issue isn’t that the new leaves are pale, but maybe the older leaves are getting dark as a sign of phosphorus deficiency. The first part of flowering needs plenty of P in their feed.
Do the older leaves have red/purple stems?

 

[Smoklahoma]

Think I over reacted. The new growth went back to normal color after 12 hours of light. Yes I do have purpling of the stems on the older fan leaves. Just changed the nutes last sat. to week 4 this sat. will change to week 5. That will be double from 3rd week on the bloom nutes. Should I add more than that?

 

[YYCannabis]

I’m not sure what you are using for nutes, but if you are switching to flower, you want to get some P values in your feed .

 

[Smoklahoma]

I'm using GH Flora trio plus thier extras. Still trying to find the proper strength to go with my lights and co2 injection. I started out at full strength and burnt them in week 2 of veg. so I backed off to 40%. I'm up to 50% now at transition. Guess I'll bump it up to 70% when i change out this weekend?

 

[YYCannabis]

Best thing is to make small incremental changes, especially with nutes. Make changes...wait...observe...rinse and repeat.