Calcium deficiency?

tmw77777 said:

From what I figure is calcium deficiency but with that I can't figure out why...
Even new leaves are spotted with brown rust spots and getting worse as it gets older.


Ph 6.0 with checked calabration
Using foxfarm cal mag as directed 5ml per gallon
50/50 Ro /tap water
Roots look healthy white and smell good but water has a little fishy smell.
General hydroponics nutes
Ppm 500
Blue dream fem seeds from Narvona.

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curious2garden said:

Get a picture of the entire plant. What's your substrate. What's your light.

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curious2garden said:

Get a picture of the entire plant. What's your substrate. What's your light.

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tmw77777 said:

Using foxfarm cal mag as directed 5ml per gallon

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tmw77777 said:

Yes I don't understand this also today I dropped my ph 5.7 in hopes that it would help.


But I'm using T5 6500k for lighting because I'm vegging and using expanded clay.
Water is about 2 inches below net pot water temp about 65 deg. Here is a few more photos.

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curious2garden said:

Ca is best absorbed at a pH of roughly 6.0 - 6.3. I pH my res down to 5.8 after 24 hours of sitting. During the course of its use it swings upward, for me usually to 6.3 It's the higher end you get Ca uptake.

NB: edited to add this chart
View attachment 5217060

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Week4@inCharge said:

This would be true in a regular soil grow, I think he's using expanded clay, an inert media, "An ideal pH for calcium to become available for cannabis plants to uptake is in the range of 5.2-5-8. This range is the general range for growing cannabis in soilless mediums".

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curious2garden said:

Ca is still best absorbed at 6.0 to 6.3. I've grown in both Leica/Hydroton and now Coco/Perlite for years. You let your reservoir swing so you take advantage of all the nutrient windows. If you're running a res below 5.5 your cannabis is suffering.

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