Yellow middles and purple stems, droopy leaves

STRAIN:bubba kush
LIGHTS:400(sunmaster) MH + three 100w eqiuv CFL for veg, 600 HPS for flower(hilux ushio), 6" Air Cooled Tube
EXHAUST:4" fan with carbon filter(inside tent) , 6" booster fan (tent exhaust hole)
INTAKE:4" fan + 4" booster fan ,fresh air from window which is about 1 feet away
TEMP: DAY(18hrs)75F-79F-RH 40-47% NIGHT(6hrs)69F-71F RH 45-50%
MEDIUM:Botanicare’s Ready Gro Moisture Formula(recommended by the hydro guy?)any thoughts?
NUTES:GH flora series +diamond nector and cal-mag for R.O water.
AGE:2 -1/2 weeks old(when i got them) fed them 400 ppm PH 6.1

Hello fellow growers!

This is my second grow and im having some issues with this bubba kush. The pictures show them yellowing on the tops and drooping didnt get pictures of the purple stems but that is another problem I have. After research i did it seems to point at magnesium deficiency but also nitrogen so im a bit confused? I was wondering if my set up had anything to do with it becasue i got them from another grow so thats why i added a list of my set up. When I got them they where nice and light green , now its dark shiny green and yellow in the middle of the leaves? can anyone help me out with this before it gets worse please! any comments , questions,or advice is welcomed! Thanks in advance

They look fine to me I don't see any yellowing, the new growth will always be a bit lighter than the older leaves. I also don't notice any drooping in the pics, its normal for a indica dom plant with fat leaves to droop a little bit. Red stems are also normal in some strains.

majek said:

They look fine to me I don't see any yellowing, the new growth will always be a bit lighter than the older leaves. I also don't notice any drooping in the pics, its normal for a indica dom plant with fat leaves to droop a little bit. Red stems are also normal in some strains.

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Thanks for the response! I hope thats the case ill try not to worry as much and let these girls grow. I will update more on my grow.