1st time grower question about leaf discoloration

[BigDog]

Hi!
Long time lurker, first time poster!

I'm having some issues with my two white rhino plants over the last week and a half. The leaves are starting to get speckled and then yellow and dead (see pics). This is only happening to my two white rhino's, and not the snow white.
One thing that I have done wrong (I think) since the begining of the grow is getting the Ph right. In a stoner move, I have been using Ph down to get the water to 6.8, AND then I added the Fox Farms nutrients. I realized that I was screwing up when I measured the Ph of the nutrient solution and it was in the low 5s!

My question is how do I fix this? How can I tell the ph of the soil to see if I'm right about the acidity? If I am right, how do I fix it? Flush with water? Repot?

Anyway, here is the info followed by pics:

What Strain is it? White Rhino (feminized seed from Nirvana)
Is it Indica, Sativa or Hybrid? What percentages?White Rhino is a powerful F1 marijuana hybrid of White Widow and a curiously strong Canadian indica strain
How Many Plants? 2 White Rhino 1 Snow White
Is it in Vegetative or Flowering Stage? Flowering
If in Vegetative Stage... How Long?
If in Flowering Stage... How Long? 5 Weeks (just started 5th wk)
Indoor or Outdoor? Indoor
Soil or Hydro? Soil
If Hydro, Reservoir size?
If Hydro, Reservoir Temperature?
If Hydro, what type of Medium?
If Hydro, what type of Setup?
If Soil... What is in your Mix? Fox Farms Ocean Forest
If Soil... What Size Pot? 3 Gal
Size (Wattage) of Light? How Many? (2) 400W HPS
Is it Air Cooled? No
Temperature of Room/Cabinet? 75-78
RH of Room/Cabinet? 35%
PH of Medium or Reservoir? Not sure
Any Pests? No
How Often are you Watering? Every other day
Type and Strength of Fertilizers used? Fox Farms feeding schedule
Size or Square Footage of Room? 2x4x6


Here is a pic of three leaves from the same plant. A lot of the leaves look like A, although its hard to tell in the photos:

This is a pic of the plant it came from. Unfortunately due to the lighting in the tent, it was kind of hard to distinguish the yellowing. You can see some of the spots.

The two white rhino plants, you can see the discoloration on some of the leaves in this pic.

Thanks for the help!

 

[BigDog]

No suggestions? Did I post this in the right forum and word the question correctly?

 

[KFeezy]

From my reading on these forums i would tell you that B is nutrient deficincy (i believe nitrogen) I have simlar to A i would also like to know =)

 

[BigDog]

The leaves start out looking like A and then end up like B.

here is a picture of another leaf of the same plant:

 

[PrairiePoet]

Not a soil grower, but looking at the https://www.420magazine.com/gallery/data/500/1134calcium-11.jpg
I'm thinking Calcium, also because you mention pH problems and you can lock out calcium with a too low of pH.

Are you using RO water or tap?

Prairie

 

[Ludacris]

The leaves start out looking like A and then end up like B.

here is a picture of another leaf of the same plant:

Classic Nutrient Burn or severe magnesium defficiency.

CHRIS.

 

[BigDog]

Maybe the White Rhino's are more sensitive to nutrients than the Snow White I have in there. I think I'm going to flush and then water with some lighter strength nutes.

I have 2 WR and 1 SW plant in there, and the Snow White looks beautiful.

Thanks for the input.

 

[Ludacris]

Maybe the White Rhino's are more sensitive to nutrients than the Snow White I have in there. I think I'm going to flush and then water with some lighter strength nutes.

I have 2 WR and 1 SW plant in there, and the Snow White looks beautiful.

Thanks for the input.

No problem. Hope all gets better for you.
(good luck).

CHRIS.

 

[McCrackin]

That's a few things. First you have o2 root problems. Second the nutes you are using are probably causing lockout.

I say cut some fat holes in the bottom of those pots. Then make the water flow. Let them dry out then recheck.