Some kind of burn or deficiency?

Guys I am back with two of my plants once again. Skywalker OG and Gelato. I’ve been watering my plants until needed now. No longer over watering. PH going in is staying anywhere from 6.45-6.50. I’ve been watering only using RO water and Cal-mag at 1tsp/gallon. They’re in FFOF soil and letting them feed off that for the first 3 weeks before I do any additional nutes. Using SF-4000 LED light temps anywhere from 70-82F. Just saw some spots on my plant. ANY IDEA on what they can be?? I did a light foliar feed in the AM using cal-Mag but wiped off any drops on top of leafs. New growth looks fine. Any help is appreciated! First two pics are from the Gelato plant and second two are SkyOG

May I ask why this focus on foliar feeding? And this particular mix to spray?

Your ph .... you are at lower end of FFOF [ it runs 6.3 ) ... I run FFOF at 6.6 / 6.7 using TAP.
It WILL buffer tap . When you use RO you still have to put cal/mag back into it .... which is in tap to begin with.

Leaf with large spots indicate the PH issue... as well as the other issue with uptake on other leaf.

hotrodharley said:

May I ask why this focus on foliar feeding? And this particular mix to spray?

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I previously had signs of a deficiency with brown spotting which seemed to be cal-mag related on these two and on some younger plants. I haven’t sprayed the younger but these two on the OP seemed to get better with the spraying.

Cal-mag strikes again and again. So you're foliar spraying cal-mag AND introducing it into the medium? Theres your issue. You are locking out essential micro and macro nutrients.

Budzbuddha said:

Your ph .... you are at lower end of FFOF [ it runs 6.3 ) ... I run FFOF at 6.6 / 6.7 using TAP.
It WILL buffer tap . When you use RO you still have to put cal/mag back into it .... which is in tap to begin with.

Leaf with large spots indicate the PH issue... as well as the other issue with uptake on other leaf.

Click to expand...

My tap water is at about 450ppm which is why I chose to stay away. When I water using R/O I add the cal-mag back into it and PH between 6.45-6.5 on a younger plant I did notice my runoff was around 5.5. Which is a huge drop in PH. I did not check runoff on the two on the OP since Last time I watered.

Highlife42 said:

Cal-mag strikes again and again. So you're foliar spraying cal-mag AND introducing it into the medium? Theres your issue. You are locking out essential micro and macro nutrients.

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So this is due to nutrient lockout?

Yes. Lower your PH next feeding to more a acidic PH for 1 time. Say 5.5-5.8. Its too concentrated with Cal-mag/alkali.. Then return it to normal without cal-mag. You need more acids now to break down the alkaline

Highlife42 said:

Yes. Lower your PH next feeding to more a acidic PH for 1 time. Say 5.5-5.8. Its too concentrated with Cal-mag/alkali.. Then return it to normal without cal-mag. You need more acids now to break down the alkaline

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Do You suggest keeping nutes in minus the cal-mag?

Depends on the ratio. Slow and steady wins the race. Thin the nutes out. Its still very early.

Thi thread is getting scary. Budz was on point. The rest???FF without lightening requires 6.2-6.6 PH. A solid flush of 5.8 to 6.0 is suggested. Then charcoal filtered or let sit out with agitation a couple times in 12 -24 hours. Will alter ppm readings. PH issues with RO and FF. People just aren't admitting it yet. And adding cal mag is just building more salts. And fish and epsoms is the best remedy till soil fix I have found.

Highlife42 said:

Yes. Lower your PH next feeding to more a acidic PH for 1 time. Say 5.5-5.8. Its too concentrated with Cal-mag/alkali.. Then return it to normal without cal-mag. You need more acids now to break down the alkaline

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This is a terrible advice IMO. First you want to lower the pH but still use "Calmag" which should only be used to raise pH and buffer peats natural acidity. You will only cause heavy pH swings which you should work to avoid.

You're contradicting yourself by your advice. You don't need extra "Calmag" in peat based soils. While it may help to buffer pH higher you could use potassium silicate instead or simply combat with running higher pH in the feeding solution. Cheers!

Wastei said:

This is a terrible advice IMO. First you want to lower the pH but still use "Calmag" which should only be used to raise pH and buffer peats natural acidity. You will only cause heavy pH swings which you should work to avoid.

You're contradicting yourself by your advice. You don't need extra "Calmag" in peat based soils. While it may help to buffer pH higher you could use potassium silicate instead or simply combat with running higher pH in the feeding solution. Cheers!

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A late night and mixing of my words. I'm not saying to add cal mag. Its already too concentrated. PH swings are actually good when done right in a living soil. Cal mag is alkaline so of course its not going to lower PH. CO3 combats acidity, therefore its gonna keep stacking alkaline metals in the soil