High pH lockout in coco - tips for reducing

[coreywebster]

So what do you think I should do? Watering at 5.8-6 is giving me shit results and I'm out of ideas.

Can you be 100% your ph meter is reliable and properly calibrated?
Can you verify with a basic ph drop test?

Does the problem get less when you flip to flower?

 

[Calbrowno]

Can you be 100% your ph meter is reliable and properly calibrated?
Can you verify with a basic ph drop test?

Does the problem get less when you flip to flower?

Yes. I have been extremely paranoid about it giving me false results and have probably calibrated 7 times in the last two weeks. And yes I can and do.

It's hard to say - the flower room is definitely the one showing signs of recovery, 75%ish of the new growth is starting to form normally and keep its shape without cupping or wilting, but older leaves are still experiencing that weird thing where salt(?) precipitates on the leaf surface and it browns off along the leaf vein, while the rest of the leaf stays greenish.

 

[coreywebster]

Yes. I have been extremely paranoid about it giving me false results and have probably calibrated 7 times in the last two weeks. And yes I can and do.

It's hard to say - the flower room is definitely the one showing signs of recovery, 75%ish of the new growth is starting to form normally and keep its shape without cupping or wilting, but older leaves are still experiencing that weird thing where salt(?) precipitates on the leaf surface and it browns off along the leaf vein, while the rest of the leaf stays greenish.

Yeah i was just wondering really to rule out the LED causing light stress, but I wouldn't image 150w of LED bars would be to much unless they are only a few inch away from plants.
Ive had times where ive had light stress and weird symptoms in veg that disappear in flower with reduced hours of light.
Probably nothing to do with what your experiencing, just worth asking though.

As for precipitation on leaves I cant say I have ever seen anything like that in my life. So that's puzzling.

I think as far as that goes your really going to have to post pics, someone may have seen it before.

 

[Calbrowno]

Yeah i was just wondering really to rule out the LED causing light stress, but I wouldn't image 150w of LED bars would be to much unless they are only a few inch away from plants.
Ive had times where ive had light stress and weird symptoms in veg that disappear in flower with reduced hours of light.
Probably nothing to do with what your experiencing, just worth asking though.

As for precipitation on leaves I cant say I have ever seen anything like that in my life. So that's puzzling.

I think as far as that goes your really going to have to post pics, someone may have seen it before.

Yeah I don't think that'll be it, if only it was that simple.

I would love to give photos but don't even have a phone at the moment to take any. If you don't mind I'll pick your brains a little bit more..

With the information I've given, it seems that it's a combination of lockouts right? And they seem to be either Iron, sulfur, possibly magnesium? which would imply that it's a lockout due to high pH? - I have a bit of reading on the topic trying to figure it out and supposedly salts can essentially solidify in the plant cell if they aren't utilized, which may be the cause of the veins dying off..


Is it normal for the pH of runoff to rise up to an entire pH level compared to the feed putting i'm putting in?

How long usually will It take to notice that a lockout has been corrected?

 

[coreywebster]

Yeah I don't think that'll be it, if only it was that simple.

I would love to give photos but don't even have a phone at the moment to take any. If you don't mind I'll pick your brains a little bit more..

With the information I've given, it seems that it's a combination of lockouts right? And they seem to be either Iron, sulfur, possibly magnesium? which would imply that it's a lockout due to high pH? - I have a bit of reading on the topic trying to figure it out and supposedly salts can essentially solidify in the plant cell if they aren't utilized, which may be the cause of the veins dying off..


Is it normal for the pH of runoff to rise up to an entire pH level compared to the feed putting i'm putting in?

How long usually will It take to notice that a lockout has been corrected?

It is normal for the ph to rise as nutrients generally lower the ph of the water and the plants taking up those nutrients.
I couldn't tell you by how much, it would depend on how strong the feed is. Higher ec there would be more nutrients not getting used so assume it would be less of a rise in ph. That my logic anyway.

I run one of my tents on a recirculating system when I have a large plant and the ph rises over the week due to the run off been higher , so I adjust with top up of lower ph and then change the res so I don't get a unbalanced nutrient profile.

If its sulphur or iron it can recover quickly. Just look at new growth.

If it were magnesium it would start lower down.

Given some of the symptoms you have I would want to rule out all stresses like bugs above and below ground.

 

[Calbrowno]

It is normal for the ph to rise as nutrients generally lower the ph of the water and the plants taking up those nutrients.
I couldn't tell you by how much, it would depend on how strong the feed is. Higher ec there would be more nutrients not getting used so assume it would be less of a rise in ph. That my logic anyway.

I run one of my tents on a recirculating system when I have a large plant and the ph rises over the week due to the run off been higher , so I adjust with top up of lower ph and then change the res so I don't get a unbalanced nutrient profile.

If its sulphur or iron it can recover quickly. Just look at new growth.

If it were magnesium it would start lower down.

Given some of the symptoms you have I would want to rule out all stresses like bugs above and below ground.

Had a rather important development...................................................

Was using 40x loupe to look for bugs -- couldn't see anything obvious
Went out and got a 100x loupe -- mites...................................................................... makes perfect sense now, not spider mites, the actual tiny mites that you cant see - the 'salts' I was seeing would be their sap

Fuck me I wish I got the better magnification earlier..

That would cause significant yellowing of new growth I assume?

If you have any tips to get rid of them they are most welcome - I have given the plants all a good dusting with diatomaceous earth so far..

 

[coreywebster]

Had a rather important development...................................................

Was using 40x loupe to look for bugs -- couldn't see anything obvious
Went out and got a 100x loupe -- mites...................................................................... makes perfect sense now, not spider mites, the actual tiny mites that you cant see - the 'salts' I was seeing would be their sap

Fuck me I wish I got the better magnification earlier..

That would cause significant yellowing of new growth I assume?

If you have any tips to get rid of them they are most welcome - I have given the plants all a good dusting with diatomaceous earth so far..

This was the question in my mind when you mentioned the salts on leaves but I have never had anything worse than thrips so wasn't sure.
Seen a lot of stuff about russet mites and the effect they have on leaves so it was a consideration.

100% an infestation that stresses the plant can cause issues with nutrient uptake too on top of the damage they cause directly.

Unfortunately I cant offer much useful advice when it comes to dealing with your pest problem but at least you've identified it and can now work toward narrowing down the culprits and treating accordingly.

Maybe have a look here , see if you can figure it out

Complete Pest Guide - Cannabis Pests, Bugs & Viruses | Grow Weed Easy

This easy picture guide will help you quickly diagnose your sick plants. Learn how to get rid of the most common marijuana pests!

www.growweedeasy.com

Wish you the best of luck getting it sorted dude.

 

[Calbrowno]

This was the question in my mind when you mentioned the salts on leaves but I have never had anything worse than thrips so wasn't sure.
Seen a lot of stuff about russet mites and the effect they have on leaves so it was a consideration.

100% an infestation that stresses the plant can cause issues with nutrient uptake too on top of the damage they cause directly.

Unfortunately I cant offer much useful advice when it comes to dealing with your pest problem but at least you've identified it and can now work toward narrowing down the culprits and treating accordingly.

Maybe have a look here , see if you can figure it out

Complete Pest Guide - Cannabis Pests, Bugs & Viruses | Grow Weed Easy

This easy picture guide will help you quickly diagnose your sick plants. Learn how to get rid of the most common marijuana pests!

www.growweedeasy.com

Wish you the best of luck getting it sorted dude.

Thank you so much for taking the time to help me out -- was good to talk it through with someone.

Honestly I can't believe I'm saying that I'm relieved it's mites, I had absolutely no idea what was going on and nothing was working!

have applied a systemic insecticide, hopefully it doesn't cook the leaves even more

Thanks again, .

 

[coreywebster]

No worries dude, just glad you got to the bottom of it.

 

[crow34!]

i feed with 1100-1200 ppm and PH 5.8-6.0. in coco (under LED). my run off is coming out at 2100 ppm with PH at 5.0 plants look fine at the moment.(i'm 3 weeks into flower) should i be trying to correct this?

 

[coreywebster]

i feed with 1100-1200 ppm and PH 5.8-6.0. in coco (under LED). my run off is coming out at 2100 ppm with PH at 5.0 plants look fine at the moment.(i'm 3 weeks into flower) should i be trying to correct this?

I work in EC rather than ppm but im assuming your using 700 scale, so your run off works out to be 3EC.
So yes give them a really good flush to get that run off back down.

Your at the point in flower where it really will start to go downhill fast.

In future make sure your getting 10% run off at least and your not letting your coco dry out between waterings.

 

[crow34!]

I work in EC rather than ppm but im assuming your using 700 scale, so your run off works out to be 3EC.
So yes give them a really good flush to get that run off back down.

Your at the point in flower where it really will start to go downhill fast.

In future make sure your getting 10% run off at least and your not letting your coco dry out between waterings.

was also thinking of dropping the feed to 800-900. (from 1.7 to 1.2). i have increased the morning water to get around 10% run off. left afternoon feed the same. what about PH, will getting nutrient level right, correct this? The big problem i have had with all my grows since changing over to LED is flower size.( thumb size. not coke cans) thank you for your help.

 

[coreywebster]

was also thinking of dropping the feed to 800-900. (from 1.7 to 1.2). i have increased the morning water to get around 10% run off. left afternoon feed the same. what about PH, will getting nutrient level right, correct this? The big problem i have had with all my grows since changing over to LED is flower size.( thumb size. not coke cans) thank you for your help.

Yeah cant hurt to drop the EC, I run 1.2 veg 1.4EC in flower, sometimes I go over that without stressing over it.
I wouldn't worry about the ph coming out, just go 5.8-6.2 going in without keeping it the same all the time and things will be fine.

What LED you running?

 

[crow34!]

Yeah cant hurt to drop the EC, I run 1.2 veg 1.4EC in flower, sometimes I go over that without stressing over it.
I wouldn't worry about the ph coming out, just go 5.8-6.2 going in without keeping it the same all the time and things will be fine.

What LED you running?
the led's are just a cheap lot from china. Shenzhen Avatar. Spectrum and PPFD work out OK. ( found them on Alibaba.)

 

[coreywebster]

White light ? QB copies?
Just wondering if you have enough light, what power you running over what area?

I never had any noticeable difference in bud size when I switched to LED.

 

[crow34!]

White light ? QB copies?
Just wondering if you have enough light, what power you running over what area?

I never had any noticeable difference in bud size when I switched to LED.

1200 watt over. 1.3mtr * 2.5mtr.

 

[coreywebster]

1200 watt over. 1.3mtr * 2.5mtr.

Actual watts of white light? What kelvin?
You run your tents a bit warmer than before?

 

[crow34!]

Actual watts of white light? What kelvin?
You run your tents a bit warmer than before?

3500k with added 730nm at end of day.

 

[CannaCountry]

If you sprayed a 'systemic' insecticide; I'd stop now and start over. Systemics go into the plant...you'll end up smoking it...no bueno. Good luck.

 

[crow34!]

3500k with added 730nm at end of day.

So the first water looks to be OK. i'm doing 1. 2 minute water half hour after lights on and no afternoon water. putting in around 7-8 ltr and getting out about 600-700 mls . Dropped the ec down to 1400 in run off. (pots are 50 ltrs.) will monitor pot weight to see if i need afternoon water.