Noob needs help identifying this deficiency (or toxicity)

[ms48130]

3 plants, 3 pics. They all seem to have a similar affliction. Can someone please point me in the right direction? Thanks in advance!

 

[Mañ'O'Green]

Looks like a potassium problem but we need more information to better diagnose the possible issue.

Please fill in this form: (copy and paste part is below, this first one tell what specifically to include)

-Problem: (brief description)
-Medium/grow method: soil; soilless-- coco, or peat based like Promix, etc. (please provide the actual product name); DWC, NFT, etc.
-Feed and supplements used: include brand, dosage/strength, frequency of feeding and watering (alone); method-- by hand, drippers, rercirc' or drain-to-waste,... N-P-K #'s too if you can!
-Water source: RO/DI; tap- dechlorinated-?..... EC or TDS reading; pH (don't bother with this on RO/DI, do bother with TDS/EC though to confirm it's working well enough)
-Strain and age
-Climate: night and day ambient T and RH%; res' temperatures; any extremes in T/RH% exposure
- Light used: HID, LED, COB, combo of,... wattage; light cycle hours (20/4, 18/6 , etc.); distance to tops....
-Additional info: PH in the root zone. How long have the plants been affected?...How fast did symptoms appear?... Anything else you think might be relevant..

--Pictures including WHOLE PLANT PICS, and troubled leaves.. use normal light or flash as other light sources ruin color rendering, critical for diagnostics! Turn off the grow lights.

✂ - - - - - - - - - - -
(copy and paste)-->

Problem:

Medium/grow method:

Feed: and supplements used:

water source:

PH in the root zone:

Strain/age:

light used:

Climate:

Additional info:

 

[ms48130]

Problem: spots on leaves, tips and edges coloring

Medium/grow method: Coco w perlite. Batch64 Fortified Micro Blend (triple washed & organically buffered). Using 3 gallon fabric pots for the GSC & WW, the Jillybean is in about a quart container.

Feed: and supplements used: Advanced Nutrients Perfect PH Sensi Coco Grow A & B, AN Voodoo Juice, AN B-52. All at 3mL/L right now, TDS is about 900ppm. The 3 gallon pots get about 5 liters, runoff is about 1.5-2 liters. The Jillybean gets about 1 liters, runoff is about 300mL. runoff TDS is between 900 and 1150, varies by plant but since they all exhibit a similar deficiency I don't think the variance is a factor (but honestly don't have a clue!)

water source: RO pH 7.0

PH in the root zone: modified by the AN Perfect PH nutes. AN says "throw away your pH pen" when using these nutes.

Strain/age: GSC Auto (3 weeks 5 days), White Widow Auto (3 weeks 5 days), Jillybean Photo (2 weeks 6 days)

light used: HLG 100 V2 quantum board, 100 watts. running 18/6 schedule. Temps average about 83, 62% RH.

Climate: indoor 2'x2.5'x5' tent

Additional info:

 

[Bob's Auto's]

You are growing in coco. Your pH is to high. Aim for 6.0 - 6.2 in the medium. Measure some runoff and see if the pH is lower or not.

 

[Mañ'O'Green]

Problem: spots on leaves, tips and edges coloring

Medium/grow method: Coco w perlite. Batch64 Fortified Micro Blend (triple washed & organically buffered). Using 3 gallon fabric pots for the GSC & WW, the Jillybean is in about a quart container.

Feed: and supplements used: Advanced Nutrients Perfect PH Sensi Coco Grow A & B, AN Voodoo Juice, AN B-52. All at 3mL/L right now, TDS is about 900ppm. The 3 gallon pots get about 5 liters, runoff is about 1.5-2 liters. The Jillybean gets about 1 liters, runoff is about 300mL. runoff TDS is between 900 and 1150, varies by plant but since they all exhibit a similar deficiency I don't think the variance is a factor (but honestly don't have a clue!)

water source: RO pH 7.0

PH in the root zone: modified by the AN Perfect PH nutes. AN says "throw away your pH pen" when using these nutes.

Strain/age: GSC Auto (3 weeks 5 days), White Widow Auto (3 weeks 5 days), Jillybean Photo (2 weeks 6 days)

light used: HLG 100 V2 quantum board, 100 watts. running 18/6 schedule. Temps average about 83, 62% RH.

Climate: indoor 2'x2.5'x5' tent

Additional info:

We know better here in the infirmary than to throw away our PH pen. How else would you know it is actually working? You need to get an Accurate 8 PH soil probe (or the clone) or a Blue Lab soil probe. If you go with Blue Lab be sure to get the correct one as they make several. Do not bother with any of the cheap ones as they do not work. Knowing the PH in the root zone is important. I would also recommend that the fertigation goes into the pot at 6.2 PH until you get a meter. Then adjust accordingly .

I think you may need to start transitioning into the Advanced Nutrients Perfect PH Sensi Coco Bloom A & B to up the P-K a bit.

 

[ms48130]

You are growing in coco. Your pH is to high. Aim for 6.0 - 6.2 in the medium. Measure some runoff and see if the pH is lower or not.

The Advanced Nutrients Perfect PH modifies the PH, it ends up around 6. I had at one time messed around with the water PH but the AN nutes brought it back to 6ish every time no matter where I started.

 

[ms48130]

We know better here in the infirmary than to throw away our PH pen. How else would you know it is actually working? You need to get an Accurate 8 PH soil probe (or the clone) or a Blue Lab soil probe. If you go with Blue Lab be sure to get the correct one as they make several. Do not bother with any of the cheap ones as they do not work. Knowing the PH in the root zone is important. I would also recommend that the fertigation goes into the pot at 6.2 PH until you get a meter. Then adjust accordingly .

I think you may need to start transitioning into the Advanced Nutrients Perfect PH Sensi Coco Bloom A & B to up the P-K a bit.

I have the Apera ph pen, AN's ad copy says you can throw it away, but I didn't of course. The AN Perfect PH does a pretty good job of bringing it in around 6.0. I'll check into the soil probe. I have the AN perfect ph sensi coco bloom A&B on hand.

I seem to recall reading that once the leaves become affected, resolving the nutes issue will not change them "back", just keep it from happening more, correct?

 

[ms48130]

Also, regarding shifting to the Bloom, as the Jillybean is a photoperiod, will feeding bloom flip that plant to flower?

 

[Mañ'O'Green]

Also, regarding shifting to the Bloom, as the Jillybean is a photoperiod, will feeding bloom flip that plant to flower?

That kind of leaf damage is permanent. Nitrogen deficiency (general yellowing) is reversible to some extent.

No, the flowering of the plant is not "driven" in any way by nutrients. The plant simply uses what it needs from what is available. The JillyBean will not flower until the night is 12 hours long. Nitrogen is a luxury nutrient. The plant will try to use it if it is there. Too much nitrogen during flower does slow down flowering because the plant tries to assimilate the nitrogen. This uses energy that it would otherwise use for flowers.