Can anyone help me diagnose my problem from these pics???......

poindexterous

poindexterous

Active Member
About half of my plants in veg are showing some leaf troubles, which look to me based on the icmag diagnosis guide most like phosphorus and/or magnesium def's. The thing is I'm using fresh GH nutrients in good water at 5.5 to 6.0pH, so nothing should be lacking there??? Just calibrated my pH meter. Temps around 80f. I top feed into perlite. All stuff that worked in the past. What could this be? Thanks!


IMG_2183.JPG
 
333maxwell

333maxwell

Active Member
Looks like a nute or PH issue, or one leading to the other. Drowning a bit perhaps?

Where are the leaves located on the plant affected?
 
W

windswinds

Member
One of my girls have the same condition as the leaf on the left. It seems funny that the new leaves are being born with this coloration. Is this a problem the plant seems very healthy otherwise
 
jawbrodt

jawbrodt

Well-Known Member
Looks like a magnesium deficiency starting, which is common. I use Calmag Plus, along with my Dynagro nutes, even though they also contain magnesium. MJ plants really seem to burn up the Mg, and since I started added extra, I've never had an issue. Might be a good idea to supplement a little more, in addition to you regular ferts.
 
poindexterous

poindexterous

Active Member
333maxwell said:
Looks like a nute or PH issue, or one leading to the other. Drowning a bit perhaps?

Where are the leaves located on the plant affected?
Click to expand...
Symptoms are from midway up to the top but new growth doesn't show it right away, not till leaves get larger. Some plants have it bad enough to pull if they don't improve, and some barely at all.

Yeah, I thought maybe too frequent watering, though perlite drains so fast. I tried reducing water cycles without improvement but maybe it didn't help cause damage was already done? Like you said it's gotta be nute, pH, or water related, I just can't figure which and why?
 
poindexterous

poindexterous

Active Member
jawbrodt said:
Looks like a magnesium deficiency starting, which is common. I use Calmag Plus, along with my Dynagro nutes, even though they also contain magnesium. MJ plants really seem to burn up the Mg, and since I started added extra, I've never had an issue. Might be a good idea to supplement a little more, in addition to you regular ferts.
Click to expand...
Hey funny you mention calmag-plus that is actually the one supplement in my rez besides my GH nutes. What ml per gallon do you add? The directions for "hydrogardens" on the container are all in various ppms, so I just went with 5ml/gal which added 200ppm total to my rez.
 
jawbrodt

jawbrodt

Well-Known Member
poindexterous said:
Hey funny you mention calmag-plus that is actually the one supplement in my rez besides my GH nutes. What ml per gallon do you add? The directions for "hydrogardens" on the container are all in various ppms, so I just went with 5ml/gal which added 200ppm total to my rez.
Click to expand...

I'm a soil grower, but, I can tell you that it's a good idea to start using the stuff early, rather than later. I start at about week 3, at 1/2 strength, then by week 4, I am at full strength, and use it right up til the end of flowering, right along with my other nutes.
 
poindexterous

poindexterous

Active Member
rosecitypapa said:
What are your npk ratio's and total ppm's? When you have to top off, is your tds rising or falling?
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I do the GH 123/321 ratio, so for veg, 3part grow, 2 microbase, 1 bloom, at about 1000ppm total, I see a very gradual drop in ppm between rez changes. Conditions aren't much different now then when they've been happy though, which is a head scratcher. Another thing is I only ever need to add pH raise to the rez, the roots seem to acidify the water, though this also happens when they're happy.
 
rosecitypapa

rosecitypapa

Active Member
poindexterous said:
I do the GH 123/321 ratio, so for veg, 3part grow, 2 microbase, 1 bloom, at about 1000ppm total, I see a very gradual drop in ppm between rez changes. Conditions aren't much different now then when they've been happy though, which is a head scratcher. Another thing is I only ever need to add pH raise to the rez, the roots seem to acidify the water, though this also happens when they're happy.
Click to expand...
That's not an npk ratio. It's different and it's can be helpful. If the ratio is off, you can get leaves like you have. So for the drop in ppm (measured before and after replenishing) means you can feed a little more, a rise in ppm means cut back. This is due to the ratio of water being used by the plant in relation to the nutrients, we're shooting for 50/50, a balanced and even uptake.
 
poindexterous

poindexterous

Active Member
rosecitypapa said:
That's not an npk ratio. It's different and it's can be helpful. If the ratio is off, you can get leaves like you have. So for the drop in ppm (measured before and after replenishing) means you can feed a little more, a rise in ppm means cut back. This is due to the ratio of water being used by the plant in relation to the nutrients, we're shooting for 50/50, a balanced and even uptake.
Click to expand...
I've never actually calculated my individual element ppm's, only monitored total ppm, guess I could find elemental ppm's if it's on the GH bottles. I just assumed the nute makers made sure it was right?

Oh wait, I see what you mean as far as the 50/50 water/nute use. I have a float valve that keeps the rez full so I see my ppm drop but water level doesn't. I could shut it off and find out which drops faster. Also there is some water loss not used by plants since they are top fed on an open surface, suppose it's not a lot though.
 
Snow Crash

Snow Crash

Well-Known Member
It is a ratio issue.
Too much Nitrogen and Potassium, not enough Phosphorus and Magnesium (actually, just less potassium and the same amount of mag probably). It could possibly be related to pH calibrations that required both pH up and pH down to be added to the reservoir. The addition of bicarbonates could cause lockups that would add to the problem.

Hydroponic issues can show up quick. If you've recently switched from 321 to 123 then I think the nutrient change is a pretty clear culprit. If you can try to alter the ratios, reducing the N and K while increasing the P and Mg that could slow the problem. I'd also suggest dropping the over all EC of the solution closer to 1.6 (800ppm) or 1.8 (900ppm).

Try to dial your environment in a little better also. If you can keep your temperatures around 76 all the time, lights on and off, that will reduce the shock of swinging root zone temperatures which can also contribute to pH fluctuations. Keep that reservoir temperature consistent, the air temps consistent, and the ratios dialed in a little better at a lower overall level... I think things will be just fine here on out.
 
rosecitypapa

rosecitypapa

Active Member
Snow Crash said:
It is a ratio issue.
Too much Nitrogen and Potassium, not enough Phosphorus and Magnesium (actually, just less potassium and the same amount of mag probably). It could possibly be related to pH calibrations that required both pH up and pH down to be added to the reservoir. The addition of bicarbonates could cause lockups that would add to the problem.
Click to expand...
Hey Snow Crash, perhaps you could clarify the last two points?

1) How does pH calibrations using both pH up and pH down contribute to this issue?

2) Is the addition of bicarbonates & lockups due to them being highly attractive bonding sites for nutrients and thus causing precipitation?
 
rosecitypapa

rosecitypapa

Active Member
poindexterous said:
I've never actually calculated my individual element ppm's, only monitored total ppm, guess I could find elemental ppm's if it's on the GH bottles. I just assumed the nute makers made sure it was right?

Oh wait, I see what you mean as far as the 50/50 water/nute use. I have a float valve that keeps the rez full so I see my ppm drop but water level doesn't. I could shut it off and find out which drops faster. Also there is some water loss not used by plants since they are top fed on an open surface, suppose it's not a lot though.
Click to expand...
lol, nute makers have waaaaaay different opinions about what ratio is right or not, thus the reason for their existence. Yeah, knowing if your ppm's are too strong, too weak or just right is another item you can cross off your list of what the problem could be.
 
Snow Crash

Snow Crash

Well-Known Member
rosecitypapa said:
Hey Snow Crash, perhaps you could clarify the last two points?

1) How does pH calibrations using both pH up and pH down contribute to this issue?

2) Is the addition of bicarbonates & lockups due to them being highly attractive bonding sites for nutrients and thus causing precipitation?
Click to expand...
2 is the answer for 1.

The Bicarbonates and the Phosphates carry a charge. It is this imbalance of electrons to protons that causes H2O molecules to break apart into H+ and OH-. Then a number of Hydrides and Hydroxides are bonded to the electrically imbalanced respective Bicarbonate or Phosphate. As a result you wind up with an imbalance of H+ or OH- atoms/molecules floating around in the solution. It is this discrepancy, or variance, of H+ to OH- that determines Acidity or Alkalinity.

So when you add a bunch of Phosphoric Acid the water molecules react, chemistry occurs, and a number of water molecules are broken apart. Adding more highly Alkaline Bicarbonates (which have no nutritional value) does little more than to grab whatever available elements are near by. This could involve creating a varied amount of different bicarbonate precipitates that form in high salt environments.

Then, by feeding this solution the plant is subjected to more of an electrical equilibrium problem more than anything else.

Remember what you know about osmosis. The root cell membrane takes in elements by electrical attraction. The media has a specific "Cation Exchange Capacity" or basically, how charged the media is. The proper pH provides the proper charge which is most beneficial to the intake of elements through the root membranes. When the media, or in this case, deep water culture is electrically imbalanced, all over the place, with precipitates and all kinds on non-nutritional molecules... The osmotic system becomes upset and as a result the plant can't get moisture and elements as readily.

Plants go into survival mode. Consuming mobile elements like Magnesium and Potassium to support the new growth closer to the top of the plant.

I hope this helps more than it confuses.
 
poindexterous

poindexterous

Active Member
Snow Crash said:
2 is the answer for 1.

The Bicarbonates and the Phosphates carry a charge. It is this imbalance of electrons to protons that causes H2O molecules to break apart into H+ and OH-. Then a number of Hydrides and Hydroxides are bonded to the electrically imbalanced respective Bicarbonate or Phosphate. As a result you wind up with an imbalance of H+ or OH- atoms/molecules floating around in the solution. It is this discrepancy, or variance, of H+ to OH- that determines Acidity or Alkalinity.

So when you add a bunch of Phosphoric Acid the water molecules react, chemistry occurs, and a number of water molecules are broken apart. Adding more highly Alkaline Bicarbonates (which have no nutritional value) does little more than to grab whatever available elements are near by. This could involve creating a varied amount of different bicarbonate precipitates that form in high salt environments.

Then, by feeding this solution the plant is subjected to more of an electrical equilibrium problem more than anything else.

Remember what you know about osmosis. The root cell membrane takes in elements by electrical attraction. The media has a specific "Cation Exchange Capacity" or basically, how charged the media is. The proper pH provides the proper charge which is most beneficial to the intake of elements through the root membranes. When the media, or in this case, deep water culture is electrically imbalanced, all over the place, with precipitates and all kinds on non-nutritional molecules... The osmotic system becomes upset and as a result the plant can't get moisture and elements as readily.

Plants go into survival mode. Consuming mobile elements like Magnesium and Potassium to support the new growth closer to the top of the plant.

I hope this helps more than it confuses.
Click to expand...

Hey Snow, that's over my head but I want to learn this stuff and understand why I get leaf symptoms. My GH pH raise is Potassium Carbonate and Potassium Hydroxide, and whenever I add it to my solution I notice a white cloud forms in reaction to it and then vanishes. You mention precipitates, that must be what I'm seeing? Is this a bad thing? Without using pH raise my solution would become too acid so I feel I must use it, but is there a different or better approach? My nutrient solution only ever drops in pH so I only ever use pH raise, the larger and faster growing my plants are the faster they acidify their nutes. What's your perspective on this? Thanks!
 
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