Please Explain

[Tokeybear12]

Both same strain in RDWC. 32 days from seed
750ppm
1.5 EC
5.8 PH
Water temp 68(chiller)
60%RH
80°f light on
73°f lights off
VPD 1.2 on average
Light height 24 inches

One is doing amazing, she's Gorgeous the other not so much. Can some give me some ideas please. 1st pic is the pretty lady other 2 are the problem child lol

 

[waterproof808]

I dont really see a problem here

 

[Tokeybear12]

So the last 2 pics show downward cupping of the top growth as well as random portions of discoloration. I think it may have been a high VPD. I was reading that those symptoms tend to mimic deficiencies. So I adjusted temp to 72.5 and RH to 62% and got a stable VPD of 1.08 for the last 24 hours so I'm hoping that fixes it

 

[hotrodharley]

You could consider some defoliation. Nothing drastic.

 

[Tokeybear12]

You could consider some defoliation. Nothing drastic.

I did do some defoliation the other day and I also trimmed up the roots as well. I was skeptical about root trimming but found that it is very beneficial in RDWC since there is a constant current pushing them in a particular direction. They seem to have responded well to the root trim. I'm not sure if I mentioned already but this is my 1st attempt at soiless so kinda nervous lol

 

[Tokeybear12]

So I'm wondering if this is root rot or dye from the nutes, because I'm having some issues with this lady still and I can't figure it out nor have I seen this before. Random splotches of yellow, they are both in the same system using same water and the other lady is doing wonderful. They are both growing 1-2 inches per day at day 45 from seed. The one lady that's doing great has the BIGGEST fan leaves I've ever seen. Side note.. is that normal?
Temp-72.5
RH- 58%
VPD- 1.08 on average during day .95 during Nighy
Water temp- 66°F(water chiller)
PH-5.8
LED lights- 28 inches.