12/12 flipped needing help!!

[CornerStone]

Hope you guys can help me out on this one. My plant leaves keep getting yellow with a burning upwards.
After a lot of research I identify this as a cal Mag def. But its been 3 weeks Im feeding her with cal mag and those leafs dont stop to show up like that.

Here is more information about my grow.

Strain: Royal Queen seeds (Euphoria CBD)

4 weeks since flip to 12/12

Temps: 23 - 25 Celsius
Humidity: 65%
7 Liter pots


the last 3 feeds in august was:

14th: 150ppm calmag, 450ppm flora nova grow. Total: 600ppm. Ph 6.4 Runoff: Ph6.0

20th: 220ppm calmag, 300ppm grow, 200ppm bloom total: 720ppm.

25th: 270ppm calmag, 330 grow, 400ppm bloom. Total: 900ppm. Ph 6.6 Runoff: Ph6.1

(Im using RO water that comes out 3ppm only) and Flora nova Series

I notice that the runoff ph is always getting lower. maybe this is the main problem?

Should I give her more nutes?



Here is some pictures:

 

[ANC]

I don't think cal-mag was your problem. It looks more like you fried the plants with fertilizer and that caused a lockout of multiple nutrients now.
What medium are you using?

 

[SouthCross]

Take soil sample. A tablespoon of soil is enough. Collect it as low in the pot as you can get, without hurting the plant.

Put the dirt in a small container. Cover with 7.0 ph water. Let sit for at least 15mins. Check the ph.

Cal-Mag can and will mask problems. Something is locked.

 

[CornerStone]

Take soil sample. A tablespoon of soil is enough. Collect it as low in the pot as you can get, without hurting the plant.

Put the dirt in a small container. Cover with 7.0 phone water. Let sit for at least 15mins. Check the ph.

Cal-Mag can and will mask problems. Something is locked.

Hey SouthCross what you mean by cover with 7.0 ph water? You mean water until fill the container?

I will do that. Thanks!

 

[SouthCross]

Hey SouthCross what you mean by cover with 7.0 ph water? You mean water until fill the container?

I will do that. Thanks!

Cover the sample of dirt with about an inch of water. You need space between the stuff that floats and the stuff that sinks. The sample has to settle to get the clearest water. It'll have some color but should be clear enough to see major colors. Like red, yellow, and green using the liquid ph indicator solution.


I vacuum a sample using a 3ml syringe with a 16ga needle from the feed store.

 

[CornerStone]

I don't think cal-mag was your problem. It looks more like you fried the plants with fertilizer and that caused a lockout of multiple nutrients now.
What medium are you using?

Im using a peat moss based soil with vermiculite. The plant seems to be eating according to runoff.

 

[whitebb2727]

Ph is a problem. With peat I get batches that do that. You need to mix some lime and humus in your next mix to help buffer ph.

Go with plain. Water for a couple watering with plenty of run off.

Start back with grow formula and cal mag. Then move to a mix of grow and bloom.

You need N all the way through.

 

[CornerStone]

Ph is a problem. With peat I get batches that do that. You need to mix some lime and humus in your next mix to help buffer ph.

Go with plain. Water for a couple watering with plenty of run off.

Start back with grow formula and cal mag. Then move to a mix of grow and bloom.

You need N all the way through.

When you say plain water you mean plain ro water?

Shoul I ph aroung 7.0ph to raise the ph of the pot?

 

[whitebb2727]

When you say plain water you mean plain ro water?

Shoul I ph aroung 7.0ph to raise the ph of the pot?

If using ro or distilled you need a bit of cal mag because its void of minerals.

Water only. Don't worry about the ph. I say you have some salt built up.

Plain water a couple or few times with good run off then start back like advised.

 

[SouthCross]

When you say plain water you mean plain ro water?

Shoul I ph aroung 7.0ph to raise the ph of the pot?

When I mentioned 7.0ph. That was strictly for the soil test. A neutral starting point. The ph of the soil itself determines what the run off ph is. To change the physical ph of the soil. Either up or down. Let's say you need it go up. You have to add a lot of PH up. Way more then it'd take to just ph the water.


You can adjust the water ph all you want. At those levels, it won't change the ph of the soil. Plus, peat moss is naturally acidic.

 

[CornerStone]

When I mentioned 7.0ph. That was strictly for the soil test. A neutral starting point. The ph of the soil itself determines what the run off ph is. To change the physical ph of the soil. Either up or down. Let's say you need it go up. You have to add a lot of PH up. Way more then it'd take to just ph the water.


You can adjust the water ph all you want. At those levels, it won't change the ph of the soil. Plus, peat moss is naturally acidic.

what ph do you recomend for my next watering??

 

[SouthCross]

what ph do you recomend for my next watering??

It doesn't matter. The water by itself, with a ph between 5.5 to 8.0, is suitable. The PH of the water has little effect on changing soil ph. It's not that easy.

The PH level of the soil is an indicator of the amount of lime. The ph of a jug of water won't change it.

 

[subwoofers]

How close are your lights to the plants, what kind of light are you using?

 

[SouthCross]

How close are your lights to the plants, what kind of light are you using?

I use four COBs. Estimated 200watts. Last grow was mix of 3000k and 3500k. The next are straight 3000k. Sprouts, 38-40". I let the plant grow into the light. Around 30", I raise the light. My last grow finished at 10.5"-11.5 tip of colas from the light. The chips could be considered at being ran at 100%.

Less then 12" in flower is pushing it. They can grow in veg just fine at 30". Closing the distance is by feel.

 

[CornerStone]

If using ro or distilled you need a bit of cal mag because its void of minerals.

Water only. Don't worry about the ph. I say you have some salt built up.

Plain water a couple or few times with good run off then start back like advised.

so a couple of flushes with ro water with 200ppm cal mag is ok?

them how much nutrients on the next watering?

 

[im4satori]

veg
per gallon max
6mls floranova grow
3mls calmag
1/8 tsp Epsom salt (0.5 grams)

bloom
per gallon max
8mls floranova bloom


it sounds like you might also be over doing it on calmag
the floranova nutes don't need much in veg 3mls/gallon is plenty and don't need any in bloom

after a ph check and a flush id feed half max strength 1 time (4mls/gallon bloom) and then full strength (8mls per gallon) every other watering there after

 

[whitebb2727]

so a couple of flushes with ro water with 200ppm cal mag is ok?

them how much nutrients on the next watering?

I wouldn't really flush heavy. Just your next couple watering water only with good run off.

Then feed grow nutes at1/4 and work back up. Cannabis needs N in flower. Not as much but is still needed.

You may have to work a little lime into the top of the soil to help buffer the ph.

 

[im4satori]

I wouldn't really flush heavy. Just your next couple watering water only with good run off.

Then feed grow nutes at1/4 and work back up. Cannabis needs N in flower. Not as much but is still needed.

You may have to work a little lime into the top of the soil to help buffer the ph.

^ yup

 

[Elvin Bishop]

Flush and skip a cycle, and then go back to whatever ppm reading you were getting before they burned. You're at 900ppm and they're burnt, so you probably have a lockout. How often are you feeding them at 900? In that medium, I'd go every 3 days, You may be giving them too long in between to feed that high. I usually peak out between 1650 and 2100 ppm depending on the strain, medium, and ID or OD. I never really get more than a few burnt tips, but I feed early and also use primarily soil. I feed every 3rd day and basically start flushing late week 5 unless I'm using a PK booster and then maybe another week. Less is more in many cases, though. I'd flush one good time with good water in the area of 6.0 for a few days and maybe skip a cycle, and then start over.

It sucks that it you're in the 4th week because you're kind of in, or on the cusp of one of the most critical parts of flowering. If you're going to burn something, try not to do it anywhere near weeks 4 or 5. I'm sure it will be fine.

 

[im4satori]

the way your describing your feeds as xxx ppm this bottle and xxx ppm that bottle
that's not how you want to use your ppm meter... I understand it sounds reasonable but it doesn't really work that way and its to much to get into at the moment

using that fertilizer

I would mix the veg nutes until one weeks into 12/12 and then switch to the bloom nutes the way I suggested

theres not really a need to mix the two veg and bloom , and the floranova bloom is not one of these low N fertilizers so it wont yellow you out early in bloom

if you mix it the way I suggested youll know the fertilizer is balanced... so all that's left is to adjust the frequency of your fertilizer additions

you could do plain water 2x and fertilize every third time, if they look hungry up the feeds to every other

make sure when you fertilize your getting 20% run off from the bottom... so if you pour in 1 gallon into the pot your looking to collect 3 cups from the bottom of the pot to prevent salt accumulation