Red stems on fan leaves

i am currently growing the strain euphoria in an indoor grow room. i grew them in a small cupboard during their veg stage and have now moved them to the attic for more space. they have been on the flowering cycle now for 2 weeks and the fan leaves's stems are turning distinctively red. is this a problem wit a nutrient deficiency? they temp varies from approx 19oC in the night and 25oC when the light is on. the top cola's are also starting to show signs of yellowing. the lights are approx 25 to 30cm away from the tops of the plants. also has anyone ever grown the strain euphoria? can you tell me your verdict on it? thanks alot

Not sure about the strain, but I'm growing some PPP and the stems have all turned red. I used MG soil, so I also experienced yellowing of my lower fan leaves because the plants had used up the nutes , so to combat it I bought Tiger Bloom from Fox Farm. ultimately the leaves will all turn yellow as the plant concentrates on the flowers.