My plant needs help

[Firstman]

I NEED HELP PLEASE WITH SOIL GROW

Strain - Blue Dream’matic
Grow Type - Soil
Grow Stage - Flower week 3
Bucket Size - 3 Gallon
Lights - 150 Watt LED
Nutrients - Advanced Nutrients - Bloom + Sensizym
Medium - 75% Perlite 25% Vermiculite
PPM - 700 (max until now)
PH - 6.5
RH - 50% to 55%

My lower leaves are color changing and the stalks are turning purple. is it nutrient deficiencies or excess?
From what I have researched it looks like a deficiency of phosphorus or potassium but I am not sure at all.

I would love for some help

 

[Dusted]

This is normal for fan leaves during flowering. The nutrients are being sucked out of the old leaves to help grow the flowers. Leave them till they wither then remove. There might be a slight magnesium deficiency due to pH of water but looks OK

 

[Firstman]

This is normal for fan leaves during flowering. The nutrients are being sucked out of the old leaves to help grow the flowers. Leave them till they wither then remove. There might be a slight magnesium deficiency due to pH of water but looks OK

Look at the stalk color and tips. is it normally at this stage? all lower leaves start changing slowly...

 

[Dusted]

As I mentioned there might be a magnesium deficiency due to the pH of your feed solution. Make sure it is 6.2. Not sure of your grow media? Do you supplement with cal mag?

 

[Firstman]

Do you supplement with cal mag?

Yes i use cal mag 1ml. I forgot to mention that I'm using using reverse osmosis water

 

[Dusted]

I see you adjust to pH 6.5. I would lower that to 6-6.2. I try to run my hydro system at 5.8, but soil should be a bit higher. You may need more cal mag since you are almost hydroponic with your mixture and no natural hardness ions. Try running pH 6.0 nutrients and water in the future with more cal mag

 

[SteveJasmine]

I agree with @Dusted definitely need calmag and your grow is basically hydroponic. I think you need to start treating it as such. Just mho though

 

[Firstman]

You may need more cal mag since you are almost hydroponic with your mixture and no natural hardness ions. Try running pH 6.0 nutrients and water in the future with more cal mag

I will do it. Thanks for the advice and help