HELP! Fohse + Athena Blended Issues

[ProperCannaCo]

Hey everyone, looking for any help in resolving our lockout issues that have plagued us in weeks 1 through 3 of flower for the last 18 months. Below are photos of the issues we've faced since we made the switch from Dimlux HPS to Fohse A3i LEDs.

Setup:
4 Rows (5x28 each)
20 Fohse 1500w A3I LED (Summer Mode Spectrum Week 1 through 5/Autumn Mode Week 6 to Harvest)
3 Gallon Pots
Canna Coco w/ 20% perlite
Athena Blended Nutrients (Feeding 1.9 EC/6.1 PH)
Temp 84 F (Leaf Surface 84 F)
Humidity 74%
VPD around 1.0
Strains: White Truffle, Cap's Cut Mac, PDX Pop Rocks, Hollywood
Handwatering

We have been aiming to follow Dr. Coco's method of achieving runoff no more than 0.3EC higher than the input feed, which flies in the face of the Athena recommendations of allowing EC to stack as high as 5EC or more.

One thought we've had over the last few runs is that our Veg lights (a mix of T5 and Spec Grade 5 bar LED's) and their respective PPFD/DLI numbers are too weak compared to the big, powerful A3i - so we tried to start this run with a 10/14 photoperiod to ease them into the transition with a slightly lower DLI than the Veg.

Instantly after flipping they showed signs of salt buildup, so we tapered down our 1.7 EC feed to 1.4 EC as we were seeing runoff numbers north of 2.1 EC. They're still transpiring better this run than any of the previous, but once again we went from a near perfect Veg cycle to signs of deficiencies within a week of flipping. As you can see, we've removed a lot of the dead or dying leaves but will say that there are several plants that are relatively happy.

Any help or suggestions would be huge!

 

[Creeperpark]

Sorry to see you are having problems friend. Your plants are suffering from water transpiration issues. The excess EC build-up is because the plants are not pushing the liquid from the soil roots up the stem and out the stomata fast as it did when you had Dimlux HPS.

If you raise the temperature and heat the area more the water should start moving again. The heat should be turned on and the vents crack open an inch or so. When doing this the warmed air will hold more moisture (RH), escape from the grow area through the vents and be replaced with outside air of lower RH. After the moisture drops and the water starts moving again the EC will drop.

It can be harmful to switch lights while the plants are growing. It's better to start fresh so the plants can acclimate only once. You can use a diluted amount of fertilizer water to flush the EC lower however you may already have root damage from the transpiration issue. I hope your plant gets better. Please keep us posted.

 

[ProperCannaCo]

We greatly appreciate the notes, Creeper. Keep you posted how things play out as we make a few of those suggested tweaks. Today was already a sign of improvement by bumping our EC up a tad on the last feed. Unfortunately, we don't have vents in our space to recirculate air that way so we just have to rely on our air movers/fans to balance our environment. But we'll make due!

 

[Creeperpark]

We greatly appreciate the notes, Creeper. Keep you posted how things play out as we make a few of those suggested tweaks. Today was already a sign of improvement by bumping our EC up a tad on the last feed. Unfortunately, we don't have vents in our space to recirculate air that way so we just have to rely on our air movers/fans to balance our environment. But we'll make due!

Are your plants still drooping heavily and continually? If they are you may have a root problem by now. Friend, please keep me posted because I would really like to know what the problem is. Thank you for sharing your hard work with us.

 

[ProperCannaCo]

Not drooping at all thankfully, friend! Even the deficient leaves are perky so that's a great sign.

 

[Crooked8]

Do you have a ppfd meter? If so what is your average would you say? Those lights are bonkers!

 

[ProperCannaCo]

Yep! They're wild haha. And yes, we sure do - the Apogee MQ500. Game changer for sure.

Also, here are a few updated pics of our room below:

It's Day 16 over here. We've lowered PH of the input to 5.9 in hopes of getting that P to move around as it appears to be part of the deficiency that's lead to the necrotic fan leaves like you described in your recent post.
86 Degrees / 74% Humidity
Leaf Surface Temp 85 to 87 degrees
VPD 1.1
Athena Blended Line
Power Si Bloom each feed
Canna Coco
IPM + Stack Foliar

I've added an image of our daily feed schedule & runoff numbers as well as the percentage we have our Fohse controller at. Just hitting 40% now here on day 16. PPFD tops out around 850 at the highest point on the canopy but average is probably 750 to 775! Lots of very healthy leaves in there and this run is FAR better than any since we installed the Fohse, but the bundle of dead ones is certainly a sign of unhappiness.

Do you have a ppfd meter? If so what is your average would you say? Those lights are bonkers!

 

[FrankyButtas]

I know one year Athena got me when they switched to “The Perfect Run” line or what not , ratios were different. Took me a week of thinking I was just winnabaketowed. Turns out I most likely was but found out never the less.

Cheers Everyone