Getting desperate, any ideas of what's wrong please

[Billpopy79]

So I'm just starting week 4 in bloom and have run into problems which are just getting worse. It started with yellowing lower fan leaves but has now progressed to upper leaves with necrotic spots and some leaves drying and falling off.
I'm now worried they won't make it to harvest.

Set up is.
440w led lighting
Dehumidifier Rh around 40%
3x circulation fans
120cfm extraction fan
Lights on 28 degrees lights off 18 degrees.
5 gal pots
Canna terra pro soil with 10% extra perlite.

Biobizz nutes
Grow
Bloom
Topmax
Heaven
Cal mag
Been feeding full recommend dosage every watering. Ph6.3

Problem has developed over the last week.
I'm pretty certain it's not incorrect watering as I follow emilyas watering guide.

After some advice here I tried lowering calmag dose.
Checked pH pen calibration and I've started using bottled water as my tap water is very hard.

Yesterday I performed a bit of a flush I watered with 5 gal plain Esther then watered with nutes an hour later so I ended up with a 5gal run off from each plant.
Nothing I have done seems to help and I'm at a total loss as to what to try next.

Any advice would be excellent thanks.

 

[SmokeLake]

Are you still giving grow nutes or just listed it? Id get ph down a bit more going in and if you just flushed and fed your going to want to wait a few days and monitor new growth. Those leaves that started to turn are never going back and plants react slowly they look reasonably healthy It will help to get pics with natural light take plant out of tent for a few pics. The good peeps here will get you back on track in no time!!
Happy420 and HappyHolidays!!

 

[MrSauga]

It looks like a mag def but it could be caused by something else and not a lack of calmag. Too much N or P increases the demand for Mg. Too much K or Ca reduces the availabilty of Mg. You said you dropped back the calmag. How much per gal were you giving it? What type of NPK ratios are you feeding the plants right now?

 

[Billpopy79]

In bloom I've been feeding per litre
Grow at 3ml
Bloom at 2ml
Calmag at 1ml
Top max at 1ml
I've also given the bioheaven a couple of times.
To be honest I'm not sure of the ratios, Ive just been trying to follow the Biobizz feed schedule.
I cut back the Cal mag last feed to around 1/8 of what it was but that seems to accelerate the issues.

Unfortunately I don't have any light other than my grow lights around my tent.
I need to set something up so I can get better pictures.

 

[MrSauga]

OK, can you give me all the NPK values on those bottles and I can run some numbers for you? For now I would go to full dose on the calmag and keep the rest unchanged until I can see what you got going in.

 

[Billpopy79]

OK, can you give me all the NPK values on those bottles and I can run some numbers for you? For now I would go to full dose on the calmag and keep the rest unchanged until I can see what you got going in.

The grow is 4-3-6
Bloom is 2-7-4
Heaven 0.91-0.18-0.24
Topmax 0.1-0.01-0.1
I have them 1ml/l calmag yesterday after the flush.

Thank you for helping.

 

[MrSauga]

The grow is 4-3-6
Bloom is 2-7-4
Heaven 0.91-0.18-0.24
Topmax 0.1-0.01-0.1
I have them 1ml/l calmag yesterday after the flush.

Thank you for helping.

OK great... I'll need the same for your calmag and top max. I think we can figure this out easy enough.

 

[MrSauga]

oops, got it now. Not much in that top max or heaven so I'm not sure what the use is. Hold on a few minutes.

 

[Billpopy79]

Are you still giving grow nutes or just listed it? Id get ph down a bit more going in and if you just flushed and fed your going to want to wait a few days and monitor new growth. Those leaves that started to turn are never going back and plants react slowly they look reasonably healthy It will help to get pics with natural light take plant out of tent for a few pics. The good peeps here will get you back on track in no time!!
Happy420 and HappyHolidays!!

Still giving the grow nutes as the Biobizz schedule says to.
I understand the bad leaves won't repair but it's definitely spreading up the plants since I flushed and fed.

 

[Billpopy79]

oops, got it now. Not much in that top max or heaven so I'm not sure what the use is. Hold on a few minutes.

This is the calmag I'm using

 

[MrSauga]

OK, so your NPK combined values, based on 4L of water(I adjusted quantities accordingly) are 2.6-3.3-3.7. So that's an NPK ratio of 3to3to3(I cant type ratio correctly because emojis dont like it) for arguments sake. Ideally you want something around 23, 13.

So to get you something closer try using this which will increase your calmag use.
3mL Grow
1.5 mL Bloom
2mL Calmag
1mL Top Max(doesn't really affect anything with the numbers since NPK values are so low)

This gives you a combined NPK of 2.5-2.6-3.2, or a ratio of 13. This will prevent the mg from being locked out if it was and give your plants a better NPK ratio. The extra calmag should help the mag def you see.

 

[MrSauga]

Depending on how well the plants like or dislike the new formula we can add or reduce accordingly. My guess is we'll be able to increase that amount after the next feeding.

 

[Billpopy79]

OK, so your NPK combined values, based on 4L of water(I adjusted quantities accordingly) are 2.6-3.3-3.7. So that's an NPK ratio of 3to3to3(I cant type ratio correctly because emojis dont like it) for arguments sake. Ideally you want something around 23, 13.

So to get you something closer try using this which will increase your calmag use.
3mL Grow
1.5 mL Bloom
2mL Calmag
1mL Top Max(doesn't really affect anything with the numbers since NPK values are so low)

This gives you a combined NPK of 2.5-2.6-3.2, or a ratio of 13. This will prevent the mg from being locked out if it was and give your plants a better NPK ratio. The extra calmag should help the mag def you see.

Excellent, this is exactly what I will feed with my next watering.

I think the topmax is just a posh molasses from what I've been told.

I'll make a note of those ratios and if I ever start using other nutes it will give me somewhere to start.

Thank you so much for taking the time to help me out.

Hopefully this should get me to harvest.

 

[MrSauga]

Right, if anything you'll be looking for signs of K def since we dropped that amount slightly, but again by your next feeding you should be able to increase that doseage. Small steps from here because you are close to the finish line and we don't want to screw the ending up!
I'm catching up at your journal now.
Enjoy your day.

 

[Calvados]

Hi. I use canna terra pro plus. The PH range for your water and nutes is 5.8 - 6.2. It’s basically like coir except you water like soil. If you aren’t doing that you will have problems.

Soil Conundrum!? I’ve read this thread a few times. It explains in detail about the medium you are using.

 

[Billpopy79]

Hi. I use canna terra pro plus. The PH range for your water and nutes is 5.8 - 6.2. It’s basically like coir except you water like soil. If you aren’t doing that you will have problems.

Soil Conundrum!? I’ve read this thread a few times. It explains in detail about the medium you are using.

Wow thank you for this, that link has really opened my eyes.
I guess this could be my main problem all along, so if I combine a lower pH with the feed ratios advised earlier it should put me back on track.

I thought something wasn't right as I have been double checking everything and couldn't understand why they were so deficient.

 

[Calvados]

You’re welcome.

I don’t use those nutes. The manufacturer should have a feeding chart.

But yeah, the wrong PH will screw things up. If it helps, I did the same thing.