Magnesiumdeffiency with HESI?

[Cyklon]

Hey guys!

I have a small coco SOG-setup that I feed with Hesi coco nutes. I adjust the pH to around ~6.0 with given dosage of the nutes. Still my plats show mg-deffiency (and a little bit of P-deffiency too) and I can't figure out what´s the problem. At first I thought it might be due to overwatering, but the past days I have given the plants alot less of the nutrientsolution (but still not letting them dry out) and yet no sign of recovery.

I have bought mg that I'm planning to use for foliarfeeding, but it seems strange that I would have to do it. The nutes should be enough, or have I made any other mistake that I have not thought of yet?

Any of you guys have experienced mg-problems with Hesis coco nutes?
Would be thankful for some discussion.

Peace~

 

[Guest]

adjust your ph lower(5.5ish) for a few feedings a week. This will allow more Ca uptake, which will help the cation exchange with the Mg and K. Mg will absorb better at the ph you are using, but not as much Ca, which is throwing your exchange outta whack.

Cheers,
SH

 

[Guest]

are ya using tap or ro water?

Pour Through Method to check ec, pH

 

[Cyklon]

are ya using tap or ro water?

I have used both. Before putting them in flowerroom I vegged them for ~1,5-2 weeks and used nutes mixed with tapwater (adjusted to 6.0 every time). I then put them in the drip-irrigation system which had a more fluctuating pH in the tank (between 6.0-6.6).
Could this be the cause of the imbalance? I use HESI for hardwater and found out my water is 6 dh which is counted (in Sweden) as semi-hardwater. Could this be a factor as well?

Btw, I also got some stats of my tapwater here. This is before mixing with nutes.
pH 8.3
GH(Ca+Mg) - 43
dH - 6
Ca - 30 mg/l
Mg - 7 mg/l

Boom!

 

[Cyklon]

So, the grow is finished and the Mg deff was due to really low pH in the growing media (4.2). So next questions is, what causes a low pH when the nutrientsolution has been pH~5.5-6.5?

Is it the fluctuation that causes it? What is the reason that salts starts to accumulate in the growing media like that?

Bless!

 

[Guest]

Sounds to me like you have some funky coco... I have never seen coco with its pH that low... Maybe someone else can chime in

 

[Guest]

I'm no expert...but I remember reading somewhere that because the coco holds the nutes...if you feed too strong....the coco will bind the nutes which will cause a ph drop. Did you do any flushes during flowering?

I am thinking of flushing at least once a month, as even a 3 week end harvest flush still doesn't seem to rid the medium or leaves of food. Most strains are still very green at harvest time.

Cheers,
SH

 

[Guest]

your nutrients droped it

So, the grow is finished and the Mg deff was due to really low pH in the growing media (4.2). So next questions is, what causes a low pH when the nutrientsolution has been pH~5.5-6.5?

Is it the fluctuation that causes it? What is the reason that salts starts to accumulate in the growing media like that?

Bless!

 

[Guest]

How much food were you actually giving them?

 

[Cyklon]

How much food were you actually giving them?

I used the dosage recommended on the bottle. The thing I suspect was the issue was the cycle of the drip-irrigation which for a week or so was at the same cycle as the light (12/12). Means LOTS of nutes, but I was told by someone here on IC that coco holds no nutes of it own. So a constant feeding with acceptable rates of nutes in the nutrientsolution should be in order. I guess that wasn't true so the high amount of nutrientsolution that was recircualted through the coco was probably the causing factor to a salt-buildup after all. What do you think?

My next question is, can fluctuating pH-levels also lead to salt buildup? I'm talking about a passive hydro with coco, like mine, with pH fluctuations from 5.5-6.5. This was what happened to me. pH on 5.5 when mixing the nutes, and after 4 days when changing the nutesolution, the pH was at 6.6 (which seems quite normal when using phosphoric acid as pH-). Please give your comments on this. Those of you that use drip-irrigation systems, how do you keep a constant pH in your solution/media?

I flushed one time, but one of the plants had spidermites so I decided to harvest early and start a new grow instead. A few of the black dominas have rooted today. Will be yummy for sure

 

[eskimo-ranger]

hey, Cyklon could you give us an update as to how the HESI nutes are working out for you... i'm thinking of getting there product like... i haven't ever grown in coco before.. do you think there worth getting for a first time coco user?

-eskimo

p.s. death to all spider mites