Magnesium?
- Thread starter 420PyRoS
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Running promix hp medium with drip feed.
PH is a bit high for rez around 6.86
1.7% magnesium roughly in feed mixture
I'm going to say PH but will happily take any other suggestions. I hear promix hp has lime to help keep a ph buffer of 5.6 or so. Idk
Prepared to drop PH... but I also have epsom salts but I don't want to over compensate this issue.
PH is a bit high for rez around 6.86
1.7% magnesium roughly in feed mixture
I'm going to say PH but will happily take any other suggestions. I hear promix hp has lime to help keep a ph buffer of 5.6 or so. Idk
Prepared to drop PH... but I also have epsom salts but I don't want to over compensate this issue.
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Soilless is pH 6.5 ie Pro-Mix/Peat/Coco Coir.
Aim for closer to pH 7.0 in veg. Closer to pH 6.3 in flower.
Cheers!
Ok so I'm probably lacking in Magnesium. I am using a lower dose feed atm in veg.
Cannabis Critically
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pH of 6.86 should not cause Mg deficiency (5.5) but it is getting close to the point you can become iron Deficient.
Well Im using one part mega crop but at half the str. I used full str on other veg plants and didnt see this issue but they were also fed at a lower PH than what I am at currently.
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Are you running to waste or recycling the reservoir? If you are running to waste, you need to measure the waste run off. And your mixing your res at too high of a ph. You need to mix your res to where the pH is 6.3-6.5. If your res mix is high I would use horticultural molasses to lower it. What about water? What's your water pH before mixing?
If you are recycling the res then your medium has a high pH. That's how your res is partially getting a high pH. The other reason your res is high is because the plants are taking up all the nutrients. You need to feed them more.
No matter what you need to feed them more.
If you are recycling the res then your medium has a high pH. That's how your res is partially getting a high pH. The other reason your res is high is because the plants are taking up all the nutrients. You need to feed them more.
No matter what you need to feed them more.
Cannabis Critically
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@Boscoe Please don’t spend your $ on anything named Mega——
If you have pH drift you have bad data as your starting point. Might not be the only problem you have but it is a problem.
Try take a step back for bigger picture. Are all of the big 9 tuned perfectly (pH, nutrient, CO2, light,
When in doubt, I always go with the experienced;@KIS for organic soil and Lauren Houston for all things mineral salts. Either are practiced at helping people with water stuff. I’m able to ask advice and follow up questions from someone with the experience and communication skills. Answers from multiple people always confuses me.
Message me if you need names and contact numbers.
If someone says I’ve seen this before, I believe they have critical knowledge to share, so no need luck, only ears.
Peace…Jeff
If you have pH drift you have bad data as your starting point. Might not be the only problem you have but it is a problem.
Try take a step back for bigger picture. Are all of the big 9 tuned perfectly (pH, nutrient, CO2, light,
When in doubt, I always go with the experienced;@KIS for organic soil and Lauren Houston for all things mineral salts. Either are practiced at helping people with water stuff. I’m able to ask advice and follow up questions from someone with the experience and communication skills. Answers from multiple people always confuses me.
Message me if you need names and contact numbers.
If someone says I’ve seen this before, I believe they have critical knowledge to share, so no need luck, only ears.
Peace…Jeff
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Cannabis Critically
Member
Why changing pH? I understand 6.5.
The minerals used in veg are more accessible at pH 7.0 compared to 6.0. Both coir and peat becomes acidic when being broken down, peat even more so with a natural pH of 3.5-4.0.
In Pro-Mix there's no reason to pH the solution starting out since the buffers like lime and gypsum will alter the pH of the medium. You have to pH compensate more in Pro-Mix compared to Coir in late flower when the buffers starts to run out. You could re-add the buffers in the plant food and back then I didn't run high Calcium and Magnesium in the feed.
It's better to follow plant response than blindly follow general rules. I often ended up feeding up toward pH 8.0 in late flower growing in Pro-Mix to not show any deficiencies.
You're building stems, foliage and structure in veg, not producing flowers.
Cheers!
If you are using a complete fertilizer and having problems I would consider changing the type of water you are using. Pro mix is buffered enough to last up to 6 months and shouldn't have any problems with pH. I have used it for years without any problems when using pure water. The best water is RO and next is Rain water but both have to fortified with cal mag.
That all depends on the plant food. I think this is a case of watering practices and feeding frequency. Letting the pots go too dry between waterings and not feeding frequent enough.
Some plant foods contains more Calcium and Magnesium than any Cal mag product and adding more will only show excess.
The best water is the water that balances out the plant food to be in pH range, if you can get away with not adding cal mag and keep pH stable and minerals in range you're doing a better job than adding excess in my book.
RO water is only needed with an inferior water source say well water with excess iron and high EC. My tap water is very close to RO and better in every sense of the word for my use adding few natural carbonates to the solution.
The reason I use RO fortifide with cal mag is to have the perfect ratio between calcium and magnesium without all the junk in the water. If you want your plant to have to swim around through impurities and search for nutrients, use tap or well water that's alkaline. Some tap water works and some don't so use whats ever works best for you. The plant above looks like it may have a problem with cal or mag ratio or both.
Ca++
Well-known member
We can both see that, so what is stopping you?
Your pH meter sounds broke. Stand it in calibration solution again, and leave it there a similar amount of time to what it takes to see the tank drift upwards. I'm pretty sure you will see the calibration solution drift upwards. Not that either really did drift. It's the meter drifting.
If you stand it in there for ages, it will settle. Then you can set the 7, and work with it to a degree.
Don't mix a salt tank higher than 6.5pH as it wants to remain acidic. This keeps the salts in solution. If you head out past 7, you start forming unwanted compounds. Our feeds are not formulated for those losses. Though in dirt, you still have the microherd to fall back on. Some time in the next week or two. Maybe a month. Which is useless for reactive feeding approaches (where you see a problem, then try and fix it)
Cannabis Critically
Member
Foliar with Epsom Salt to green them up and keep ph adjusted to 6.5 for Promix HP. If the problem persists I would look at the nutrients I am using.
Good luck with your grow.
Good luck with your grow.
Changed 5gal supply rez feed water (no return to rez) to full str feed per gal, added half str of cal/mag and dropped PH to 6.5
I am reading it takes 7 - 10 days before the buffers like dolomite lime in promix hp to activate which is around the time frame I am at now with these clones.
Anywho, Ill update in a few days and see if all goes well or shit.
Thx everyone!
I am reading it takes 7 - 10 days before the buffers like dolomite lime in promix hp to activate which is around the time frame I am at now with these clones.
Anywho, Ill update in a few days and see if all goes well or shit.
Thx everyone!
