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Possible Magnesium deficiency in Coco or PH?

oaktree

Active member
Growing in a 3 gallon cloth pot in Mother Earth coco 70/30 perlite. My water is from a well and we have a water softener using diamond salt iron fighter. When I oh tested my water is was reading at 8. I ph’d my nutrient solution to 5.8/5.9. Im using a drip system with a 1.6 gallon reservoir. When I tested the PH of the reservoir after a few days it was like up to like 7.5. I’m not sure if my PH pen is messed up or if it’s actually that high. But I’ve read that the PH will change after going through the coco and the roots. I’m going to get some PH drops to test that way to confirm if the PH pen is working correctly. I calibrated it about two weeks ago. I’m not sure if this is a possible magnesium deficiency or a PH problem. Any thoughts?

It looks like the yellowing is on the tips of new growth too. Otherwise it’s growing pretty nicely and bushy.

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Dime

Well-known member
Premium user
I don't know much about it but 8 seems high for softened water,6 1/2 -7 would be the target other wise you still have hard water and the plumbing problems associated with it. Have you used softened water before? I was always under the impression it essentially dries plants out because it adds salt. I think you can buy different pellets to replace salt pellets.
 

oaktree

Active member
I don't know much about it but 8 seems high for softened water,6 1/2 -7 would be the target other wise you still have hard water and the plumbing problems associated with it. Have you used softened water before? I was always under the impression it essentially dries plants out because it adds salt. I think you can buy different pellets to replace salt pellets.

From what I’ve read the softener doesn’t affect PH. The hardness is due to the minerals in the water, I have high iron continent in my water. This is my first time with coco and I’ve never had a water softener before. You can buy other pellets but the amount of sodium in the water isn’t from the softener is pretty negligible.
 

PadawanWarrior

Well-known member
Interesting. I’ll see if I can try that. What about adding cal mag to the tap water? I just recently added a light dose to my nutrient solution.
Adding Epsom salt would help temporarily. But you really want to use your well water before it gets softened with sodium chloride. I wouldn't use CalMag with well water unless you know you need more Ca, and your well water probably already has enough. Plus Ca is also antagonistic towards Mg.
 

oaktree

Active member
Alright, I found the access to my well water before it hits the softer. It also happens to be before the micron filter so the water is essentially unfiltered straight from the ground. I swapped out most of the rez water with the fresh pre-softened water so we’ll see how it looks in a few days. Thank you for the help!
 

PadawanWarrior

Well-known member
Alright, I found the access to my well water before it hits the softer. It also happens to be before the micron filter so the water is essentially unfiltered straight from the ground. I swapped out most of the rez water with the fresh pre-softened water so we’ll see how it looks in a few days. Thank you for the help!
You added nutrients to it though right?
 

Ca++

Well-known member
Looks more like a potassium deficiency to me.
I don't see any strong suggestion it's Mg. I see a few signs, that point to the softener as a common cause. So I don't feel the diagnosis of which deficiency important, as the problem is antagonism. Not deficiency in the supply.

I think a tissue sample would be the only conclusive answer. Just about every feed element is a metal, that Na will block, and cause loss of colour between the veins. This plant even has loss of colour at the vein. Stubby leaves. There is a bit going on.

The pro grower is often the guy that knows he doesn't know. But does know when to use a labs help. Tradition wisdom told us that problems between the veins are Mg, but it's not that simple. Here the interveinal colour loss isn't forward on the leaf, towards the tips.
 

oaktree

Active member
I'm near as damn it 100% sure the softener caused this.
Why do you have one? It sounds like you are targetting iron, but it's not high.

They told me the water was hard and it would be better for my appliances to soften the water. They were targeting the iron and manganese with an ion exchange system.
 
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Ca++

Well-known member
They told me the water was hard and it would be better for my appliances to soften the water. They were targeting the iron and manganese with an ion exchange system.
I see, it's the Mn. The waters not hard in general, but that one is above standard.

I don't imagine the Fe or Mn levels will bother our plants. They may actually like it. If Mn was in excess, it antaganises Fe. However, you also have raised Fe. Raised Fe can put demand on P.
It's not a lot to water (edit: Watch) for. Just Fe really, and our plants have surprised the utar saint with their ability to get Fe, so much so, he thinking pH6.3 is as much use as pH5.8 because getting Fe is that easy. A higher pH would also make Mn uptake harder. I have done a run at 6.3 recently, and was pleasantly surprised.
 
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