Yellowing tips and brown spots on newer/higher growth?

Day 33 Chemdoggin x CDLC autoflower by Mephisto
50/50 coco/perlite mix
Canna A & B with CalMag
5.8 - 6.2 pH tap water
850ppm for last 2 weeks
4x4 tent, 4x QB96 v2 with canopy getting around 50-60k lux
Started feeding 5ml/gal CalMag with my A & B around 2-3 weeks ago, this problem just popped up over the last few days

Lower growth looks fine and it's not all over the plant. I'm thinking maybe too much light? The other chemdoggin x cdlc next to her that's a few inches shorter doesn't have this problem and their being fed from same reservoir

Sorry for the pics, the lights are so bright and make it seem more yellow than it is

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Gwhiliker

Well-Known Member
just figure out which one has pore phos and add less of that for a bit till it mellows out or till you flop into flower id assume, not really the person to give advice on that matter lol
 

Budzbuddha

Well-Known Member
Very minor tip burn ... ignore it.

Carry on with grow .... if you start trippin over every little tiny blemish , you might do something drastic and really screw plant.
Most “ major “ leaf issue will show very prominently.

However , rope in that range of ph and not have such a large swing.
 

Gwhiliker

Well-Known Member
Very minor tip burn ... ignore it.

Carry on with grow .... if you start trippin over every little tiny blemish , you might do something drastic and really screw plant.
Most “ major “ leaf issue will show very prominently.

However , rope in that range of ph and not have such a large swing.
listen to him^
 
Very minor tip burn ... ignore it.

Carry on with grow .... if you start trippin over every little tiny blemish , you might do something drastic and really screw plant.
Most “ major “ leaf issue will show very prominently.

However , rope in that range of ph and not have such a large swing.
I was thinking the same, especially since they're starting to go into flower. The second plant is much better, but also a little smaller
I'm struggling with it because I'm using autopots and a 12gal res. The ph constantly drifts up and I have to adjust every few hours lol
 
So it turns out my Bluelabs ph pen was shot and giving me bad readings lol..... Just over a month old and cared for properly.
My res was somewhere between 4.0-5.0 for 1-3 days I believe :(

Got a new pen and got everything situated. Raised the lights just in case
 

polishpollack

Well-Known Member
are you sure the 5 of calmag is necessary? how much of each is in A,B? 7ml + 5ml is a high ratio of calmag to base ferts, especially if AB has those already.
 
are you sure the 5 of calmag is necessary? how much of each is in A,B? 7ml + 5ml is a high ratio of calmag to base ferts, especially if AB has those already.
I'm not sure at all lol, this is my first hydro grow. I just found some threads and went with what others did

4.5% CA in the canna A, 1.1% mag in canna B

I just mix it all in my res and ph down. 700-800ppm
 

polishpollack

Well-Known Member
Frankly, I think your plant looks pretty good. Personally, I've never seen 5 out of 12ml be calmag. If A,B have cal and mag already, giving much more might be excessive but as long as things look good, it doesn't really matter. Maybe it's a good thing in coco. btw, I don't know if that amount is incorrect. I thought that it seemed high but oh well.
 
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