Yellow new growth. What is going on?

[Efbespn]

Third try at this, went super conservative on this one. Yet the yellow seems to show up, no fail not sure what to do. Signs point to potassium deficiency, but would like some guidance how to go about it.
Here's the setup
Lights : Electric Sky es300 (300watt LED) dimmed at 30%
Medium : mix of Fox farms Ocean forest and Happy FROG and perlite.
Nute: Humboldt secret base A&B
CALMAG and Iron
Real growers recharge
Impello Tribus Microbes
RO water supplemented with 4ml per gallon of cal mag and iron.
Foliar sprayed with Epsom salt 1/4 tsp per liter.thinking it's a calmag issue.
Ph at 6.4
Havent yet gave them nutes as the fox farm soil is still fresh from a recent transplant from solo cups to 1/2 gallon pots.

Room Temps at 82 RH at 70-80%

Need some help from the experts. Been digging through old post in all forums but can never get a definitive answer as to what is going on. I'm sure I'm not the only one who has run into this problem, I'd appreciate if someone who could share their expertise in finding a remedy. Thank you loads and good luck to you all on your grows. All the best!

 

[TanzanianMagic]

Third try at this, went super conservative on this one. Yet the yellow seems to show up, no fail not sure what to do. Signs point to potassium deficiency, but would like some guidance how to go about it.
Here's the setup
Lights : Electric Sky es300 (300watt LED) dimmed at 30%
Medium : mix of Fox farms Ocean forest and Happy FROG and perlite.
Nute: Humboldt secret base A&B
CALMAG and Iron
Real growers recharge
Impello Tribus Microbes
RO water supplemented with 4ml per gallon of cal mag and iron.
Foliar sprayed with Epsom salt 1/4 tsp per liter.thinking it's a calmag issue.
Ph at 6.4
Havent yet gave them nutes as the fox farm soil is still fresh from a recent transplant from solo cups to 1/2 gallon pots.

Room Temps at 82 RH at 70-80%

Need some help from the experts. Been digging through old post in all forums but can never get a definitive answer as to what is going on. I'm sure I'm not the only one who has run into this problem, I'd appreciate if someone who could share their expertise in finding a remedy. Thank you loads and good luck to you all on your grows. All the best!

I don't know what the size of the pots is, however they need to be at least 1 gallon per expected foot of growth - if you want to avoid nutrient deficiencies.

Also, you should check the first drops of runoff for pH and EC/PPM.

Also, 6.3 is too low a pH for vegging and flowering. You should go for 7.0 in organic grows because it increases takeup of P (roots) and K (stems).

In fact you should transplant into bigger planters with a higher pH and just give them some flowering food and watch them take off.

 

[Creeperpark]

You are using the wrong fertilizer with your mix of Fox farms Ocean forest and Happy FROG and perlite. Humboldt secret base A&B is not made for Fox Farm because of the type of nitrogen used. You will have problems until you use the right products together. Also spraying Epsom salt on a plant that is fed the wrong food will not help either. You will continue to have problems on this grow using your method.

 

[Efbespn]

You are using the wrong fertilizer with your mix of Fox farms Ocean forest and Happy FROG and perlite. Humboldt secret base A&B is not made for Fox Farm because of the type of nitrogen used. You will have problems until you use the right products together. Also spraying Epsom salt on a plant that is fed the wrong food will not help either. You will continue to have problems on this grow using your method.

I haven't fed them yet any nutes. Giving the ffof its time to use up its nutrients before I start using any humboldt

 

[Creeperpark]

Hungry Plants

Hungry Plants

Those plants are hungry and you need to start feeding them. I'm sorry, "What kind of water are you using"?
My Brother, when first starting out its best to use a "complete outfit" instead of many different manufactures. Don't mix potting soils because they are researched very intensely and studied by professional horticulturist's to give a certain result. If you put one potting soil with another or add a different fertilizer you will knock the (CEC)-(cation exchange capacity)" out of whack. When Fox Farms made their line it is to only be used with their nutrient line to fit the pH of the substrate and the fertilizer together. In the long run you are costing yourself a lot of time and money and most of all precious seeds.

You have to go with what you got now so "What kind of water are you using"? What is the pH of the Fertilizer mixed with water? If you would like my help.

 

[Tonygreen]

Fox farm. Peat and coco mix not garden soil.
Feed at 1.2 ec and ph to 5.8 and let it swing up.

7 is too high in peat based medium. Acts more like hydro than field dirt.

Gonna have to prune damaged leaf and let healthy grow in.

 

[f-e]

I don't really like narrowing down deficiencies. If you look at the various guides, it's hard to find any that agree. A Uni just claimed to do the first reliable article, by pulling individual things out and waiting. Non of their results caused spotting. Not calcium. Nothing. So trying to give you the answer, would just be amateurish.

I'm seeing signs in common with those reported as K, Mg and Zn. You have Mg and response times to a spraying are rapid. If the issue gets worse on the one you spray, it's likely K as they push each other out. I quite fancy Zn, but there should be enough really. It's a trace element so a trace mix usually contains it, but not the other two. I would arm myself with some, then you can see if any of the 3 are actually to blame.

 

[paradoxlost]

I don't know what the size of the pots is, however they need to be at least 1 gallon per expected foot of growth - if you want to avoid nutrient deficiencies.

Also, you should check the first drops of runoff for pH and EC/PPM.

Also, 6.3 is too low a pH for vegging and flowering. You should go for 7.0 in organic grows because it increases takeup of P (roots) and K (stems).

In fact you should transplant into bigger planters with a higher pH and just give them some flowering food and watch them take off.

This isn't necessarily correct. If you feed with every watering you can get 6 foot plants with an 8 cu. ft. pot.



Yellow new growth is normally an iron issue, but the leaves aren't very spindly, so either its very early iron deficiency, or just a general metal out of balance. I would foliar spray an Fe/Mo/Zn/Mn mix.

 

[Creeperpark]

If you have deficiencies when using a complete fertilizer, your pH is off. A complete fertilizer will not have any deficiencies.