New to indoor growing

[OldFart1971]

Hey folks, I'm new here and am loving everyone's pics and info. Seems like a cool community.
I haven't grown indoors for over 20 years and have been doing outdoor for a long time with hit or miss results depending on the weather that year and strains involved.
So I have decided to try my hand at growing 2 plants from a couple magic seeds from a bag. I'm a couple months along now and things are going pretty good considering it's new to me.
This is my setup.
A 3ft X 3ft X 7 foot tall space.
1000w MH for veg 1000w HPS for flower.
One plant in a 5 gallon and the other in a 7 gallon.
A peat, sphagnum, coco , perlite, kelp grow ,medium.
Iguana Juice Grow/Bloom.
6.5PH though I do go a bit higher or lower if I notice a nutrient issue.
Pink Kush X Sherbert

The 2 seeds seemed to produce two totally different phenotypes. One taller and a bit more sativa looking where the other is short a bushy like a pure indica.
Now at the beginning of week 5 of flowering the taller one is starting to turn more yellow with some leaves falling off while the other is going purple with no leaf loss.
It's been a learning curve but I think ots going well. 4 weeks to go.

 

[Modest Grower]

What's your temps? I'm guessing cold at night? 65F ish?

 

[Modest Grower]

That indica looks legit! I don't know enough but my gut wants to tell me the sativa is a bit hungry if not overwatered

 

[Modest Grower]

 

[Ghefredo]

It look like a light burn kinda I could be wrong and maybe she is hungry might have to go up on feeding

 

[OldFart1971]

My temps are about 65 at night and 78 when the lights are on. Both plants are the same strain just different phenotypes. The Sativa looking one has a bit of nitrogen burn. Has some of "the claw" but it's getting better after a week of straight water. The indica looking one is a heavy feeder while the other isnt which is probably why one is having a bit of nutrient issues. I have also moved the more sativa looking one farther from the light which seems to help.

 

[Danarano]

I run my ph at 6.2 during veg then 6.5 for the first half of flower then 6.8 the last half. I find the acidity in the soil rises as ferts build up in the soil and this plan really works for me