Lockout? Cal-Mag Deficiency? How to diagnose and deal with?

[zipperdoyle]

Trying to figure out what the leaves are telling me. I'm assuming it's a Cal or Mag deficiency or possibly a lockout? Appearing on the leaves that are closest to the lights. The other plant in the tent is showing minor signs of it. I'm feeding from a reservoir so a little confused on how to approach fixing this and if it's a major issue. Any recommendations?

Plant Info (Mephisto forgotten cookies):
Day 58.
Growing in 100% coco in 5 gallon autopots.
Feeding RO Water.
Doing light feeding schedule recommended by canna. This week is: 7ml A+B, Boost 4ml, Calmang 5ml, PK 13/14 5ml per gallon.

 

[DogterB]

I don’t have an answer for you but I’m interested in any responses as well. I seem to get the same thing around the same time frequently.

 

[DCLXVI]

What's the pH of the nutrient feed you've been giving them?

 

[Weedname]

Hello @zipperdoyle

May i ask how much light your girls are getting at the tops and what the total EC they get is?

Sometimes when the girls get to much light during veg/stretch/bloom - blotches like those on your leafs can occure…

In this case it could be a mix of a slightly wrong dialed in ph and a bit of to much lightning. Are you running them at 24/0?


If it were me i would have raised base-nutrient, then raised the light a little bit until she got green again (1-3 days).

It difficult to give advices online as i don’t have all the different aspects in front of me, but raise the lights and base and let her relax a bit and you should be fine.

 

[zipperdoyle]

Hello @zipperdoyle

May i ask how much light your girls are getting at the tops and what the total EC they get is?

Sometimes when the girls get to much light during veg/stretch/bloom - blotches like those on your leafs can occure…

In this case it could be a mix of a slightly wrong dialed in ph and a bit of to much lightning. Are you running them at 24/0?


If it were me i would have raised base-nutrient, then raised the light a little bit until she got green again (1-3 days).

It difficult to give advices online as i don’t have all the different aspects in front of me, but raise the lights and base and let her relax a bit and you should be fine.

Good point, I forgot to include the EC, PH, and light schedule.

EC: right around 1.9 right now.
PH: 5.8
Lights are on (HLG 300l rspec): 18/6, the girls are asleep right now but the DPI was in the 50's (I know that's high and need to double check).

Here are some pics from the other day. The left one is the lady with the most splotches. She's about 8" away from the lights right now. Her neighbor on the right (Jammy Dodgers) is flowering a bit faster.

 

[Weedname]

Good point, I forgot to include the EC, PH, and light schedule.

EC: right around 1.9 right now.
PH: 5.8
Lights are on (HLG 300l rspec): 18/6, the girls are asleep right now but the DPI was in the 50's (I know that's high and need to double check).

Here are some pics from the other day. The left one is the lady with the most splotches. She's about 8" away from the lights right now. Her neighbor on the right (Jammy Dodgers) is flowering a bit faster.

View attachment 1547634View attachment 1547635

After looking at your pics i would highly recommend you to raise that light, or keeping it much further away but then with increased intensity. It’s an easy fix and make sure the roots get enough water.

 

[JP1]

My experience with autopots is they tend to lockout at this stage of life. Plus your ec is pretty high, should be more like 1.1. Have you checked your runoff? And are those fungus gnats?

 

[zipperdoyle]

My experience with autopots is they tend to lockout at this stage of life. Plus your ec is pretty high, should be more like 1.1. Have you checked your runoff? And are those fungus gnats?

It's my first run on autopots so I'll go back and look at the EC recommendations in the forum. I thought my EC was pretty aggressive.

Is there a way to check runoff in an autopot? Would I just measure what's floating in the autopot pots?

And yes those are wonderful fungus gnats. I think I got most of them and was forced to put sand topping on the pots. I have the yellow sheets to collect any lingering ones, but only a few left.

I also think my DLI was quite high for the plant on the left (50's) and the one on the right is in the mid to high 30's so I'm going to try to raise up the smaller plant to get a more even canopy for both plants. One took off in the stretch and outgrew her sister. Again, appreciate everyone's feedback.

 

[Lil Dab]

It's my first run on autopots so I'll go back and look at the EC recommendations in the forum. I thought my EC was pretty aggressive.

Is there a way to check runoff in an autopot? Would I just measure what's floating in the autopot pots?

I don't think that will work you would need to empty the trays and fertigate from the top and then measure the runoff that comes out of the pot afterwards... I've done where I just remove the pot from tray and feed over top of something to collect the runoff or have seen folks just use a shop vac to clean the trays out and then just top water right in the trays

 

[American Hillbilly]

I battle these spots from time to time. I believe them to be caused by lockout of calcium due to an overabundance of phosphorous. I have all but done away with them by properly buffering my coco, making sure I get plenty of run off (DTW which doesn't apply here), and watching any bloom nutrients for the amount of phosphorous they have.

Certain strains/plants are more prone to it than others. This has been my experience anyway.