Mysterious necrotic spots

RuggedWombat

Well-Known Member
Imho....you're feeding too much. Try not to make it complicated. Carry on with what you were doing. But don't feed full strength, back it off to 75% or less or something. See how that goes. Remember every plant/strain different.
Which further sucks this grow as it's nothing but freebies and a m/f rando so no idea what I'm working with currently lol. I think the old homebrewer wisdom of 1/2 tsp of foliage pro is a great foundation point and then just add a bit of mag pro if plants get hungrier. I highly doubt they would need even MORE nitrogen. Next feed I may run a couple gallons of fresh PHed water through and then run a feed similar to what I ran today.
 

Billy the Mountain

Well-Known Member
Is this a tool you can just plug and play hypothetical numbers? Also the foliage pro calcium debate is impossible to figure out as it's been going back and forth on these forums for years now. Every person who says it doesn't have enough calcium is met with pictures of perfect plants who disagree. I've seen plenty of people who used nothing but foliage pro from start to finish with amazing results and 0 calcium issues. I've seen plenty of others who swear they had nothing but brown spots with just foliage pro so I really have no clue at this point. Just like PH in Promix. One school says 6.1-6.5 and another says like 5.5-5.9 and yet both still seem to work. I mean I'm competent enough to get great results, but it continues to get frustrating that I can't seem to ever be truly issue free...always something.
It's just a spreadsheet, and they're very real numbers.

There's no debate that FPro has 2% Ca, about 1/3 of of other nutes; whether that's enough or not depends on the water and the plant.

Your input EC is way too hot. Check your runoff EC for a peek to the actual rootzone EC, it's likely even higher.
 

LeastExpectedGrower

Well-Known Member
I'm not so sure it is a ph issue though. I ran 6.3-6.5 PH Promix for 2 grows straight and even though they had issues for awhile, they finished with outstanding results. If anything doing feed water feed probably caused more issues as that means they went around a week between feedings when I watered every 3 days.

I will say though moisture stress seems likely. I did a fresh water feed and then a light feeding around 400 PPM and they seem to be bouncing back, especially new growth. Though I KNOW there is a mag issue after starving them a bit. Just look at that interveinal chlorosis. My plan going forward is to water more frequently and cap the amount of foliage pro at 1/2 tsp per gallon. If the plants start to show deficiencies now that they are in flower, I can add a tiny bit of mag pro.

11/24 F8
3 gal water
1/4 tsp PT per gallon
1/4 tsp FP per gallon
1/8 tsp MP per gallon
6 PH
370 PPM

11/27 F11
3 gal water
1/8 tsp PT per gallon
1/2 tsp FP per gallon
1/8 tsp per gallon
6.3 PH
830 PPM
I guess keep doing what you're doing then, you seem to have it fully under control?
 

LeastExpectedGrower

Well-Known Member
I'm open to all feedback so please don't take it the wrong way. It was more of a general comment on how there seems to be so much contradiction when it comes to Promix PH.
Generally speaking the RIU wisdom on ProMix HP as it's a 'soilless' medium is to treat it as hydro when it comes to pH. Took me a few grows to internalize that information, but once I did, things were much easier. That said, I think you need more calcium and also adjustment to your feed strength.
 

RuggedWombat

Well-Known Member
Generally speaking the RIU wisdom on ProMix HP as it's a 'soilless' medium is to treat it as hydro when it comes to pH. Took me a few grows to internalize that information, but once I did, things were much easier. That said, I think you need more calcium and also adjustment to your feed strength.
Generally speaking the RIU wisdom on ProMix HP as it's a 'soilless' medium is to treat it as hydro when it comes to pH. Took me a few grows to internalize that information, but once I did, things were much easier. That said, I think you need more calcium and also adjustment to your feed strength.
I'm thinking one variable at a time. Run a solid amount of water through and probably start monitoring PH trends over time from runoff to see what direction it might be drifting. My runoff catches already have some build up so runoff PPM is a bit trickier. I may attempt 6.2 or even 6.1 PH, but I want to limit the amount of changes so as not to overwhelm the plants. I'll be using 1/2 tsp FP per gallon with some protekt and if the plants get hungry further in flower I'll supplement with mag pro so as not to add even more nitrogen overload. I believe the 1/2 tsp of FP with my tap ppm comes out to about 500 even which is a pretty healthy amount I'd say. The feed chart leans hard on bloom but it has bad issues with salt build up in the bottle so I'm discontinuing use of the bloom.
 

LeastExpectedGrower

Well-Known Member
I'm thinking one variable at a time. Run a solid amount of water through and probably start monitoring PH trends over time from runoff to see what direction it might be drifting. My runoff catches already have some build up so runoff PPM is a bit trickier. I may attempt 6.2 or even 6.1 PH, but I want to limit the amount of changes so as not to overwhelm the plants. I'll be using 1/2 tsp FP per gallon with some protekt and if the plants get hungry further in flower I'll supplement with mag pro so as not to add even more nitrogen overload. I believe the 1/2 tsp of FP with my tap ppm comes out to about 500 even which is a pretty healthy amount I'd say. The feed chart leans hard on bloom but it has bad issues with salt build up in the bottle so I'm discontinuing use of the bloom.
I have really high EC water and spent a lot of time screwing around trying to get it to work as-is. Theoretically, it is high in calcium carbonate (well water) but I was having calcium issues with it. I've never been so sure that what is in the water is bio-available no matter what people say. So I ended up filtering my water down to zero. I don't have a R/O setup but put it through a zero water filter. From there I add Ca/Mg, a bit more epsom salts and my nutrient. That's been my best process for success. Not cheap, but workable. I move between hand watering or using a blumat Tropf drip system.
 

Grojak

Well-Known Member
I’d go with the salt build up theory someone else mentioned and I base this on your feed schedule:

“Feeding is 100% of DG feed chart with no fresh water feedings in between nutrients”

I’ve have probably 9 years of Promix experience across I believe 4 different lines GH Flora (can’t say 100% I used Promix with this 13 years ago) FoxFarm, Botanicare and BioBizz.

I used to do nutes every watering and unbeknownst to be I had bad salt build up and crazy high run off numbers. I corrected both of these with a 2:1 cycle. 2 feed, 1 ph’d water in veg and flower. I never had plants show any signs of nutrient deficiency outside of Nitrogen with certain strains, I corrected this with a top dressing of 10-0-0 Bat guana around werk 4 on the longer flowering strains 70+ days). Of course you don’t know what you plants need until they tell ya so dialing it in on subsequent runs is important.

Also, company feed charts are usually way too hot, back it off until your plants tell ya you need more, you’ll be amazed (likely) at how much les they need, which is money in your pocket.
 

pegboy

Well-Known Member
Imho....you're feeding too much. Try not to make it complicated. Carry on with what you were doing. But don't feed full strength, back it off to 75% or less or something. See how that goes. Remember every plant/strain different.
I've been running Dyna-gro for a long time (even back in the 90s). grow, bloom, pro-tekt, and Mag-pro. litterally run usually just under 1/2 of recomended dose with a recirculating ebb and flow with rockwool and tap water (prox 250ppm). I rarely if ever get over 1.0 EC (usually lower .8 or.9). That seems to be the sweet spot for most cultivars.

edit: In my system anyway. I would say lighter is always better.
 
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NanoGadget

Well-Known Member
I'm open to all feedback so please don't take it the wrong way. It was more of a general comment on how there seems to be so much contradiction when it comes to Promix PH.
Not sure I've seen the contradictions you're referring to. I've been running promix on and off for over a decade and myself and most everyone I've ever discussed it with has been in agreement that a range of 5.8 to 6.2 is optimal. Perhaps there is a new batch of growers on here saying otherwise that I just haven't noticed, but what I can tell you for certain is that when I've kept my inputs in that range I've had nothing but smooth sailing, when I haven't problems have arisen without fail. Just my 2 cents. Good luck.
 

RuggedWombat

Well-Known Member
I’d go with the salt build up theory someone else mentioned and I base this on your feed schedule:

“Feeding is 100% of DG feed chart with no fresh water feedings in between nutrients”

I’ve have probably 9 years of Promix experience across I believe 4 different lines GH Flora (can’t say 100% I used Promix with this 13 years ago) FoxFarm, Botanicare and BioBizz.

I used to do nutes every watering and unbeknownst to be I had bad salt build up and crazy high run off numbers. I corrected both of these with a 2:1 cycle. 2 feed, 1 ph’d water in veg and flower. I never had plants show any signs of nutrient deficiency outside of Nitrogen with certain strains, I corrected this with a top dressing of 10-0-0 Bat guana around werk 4 on the longer flowering strains 70+ days). Of course you don’t know what you plants need until they tell ya so dialing it in on subsequent runs is important.

Also, company feed charts are usually way too hot, back it off until your plants tell ya you need more, you’ll be amazed (likely) at how much les they need, which is money in your pocket.
Not sure I've seen the contradictions you're referring to. I've been running promix on and off for over a decade and myself and most everyone I've ever discussed it with has been in agreement that a range of 5.8 to 6.2 is optimal. Perhaps there is a new batch of growers on here saying otherwise that I just haven't noticed, but what I can tell you for certain is that when I've kept my inputs in that range I've had nothing but smooth sailing, when I haven't problems have arisen without fail. Just my 2 cents. Good luck.
Here's a few for starters. Again I'm not saying one way or another. I'll do whatever keeps my plants healthy, but I did want to illustrate how confusing this place can be to navigate at times.





.991707/
 

cannabiscrusader

Well-Known Member
I would drop the mag pro. Your dynagrow and your foliage pro already have magnesium in it. The extra mag is probably blocking out calcium. Do you foliar spray with any of it? Some of that mottling looks like light damage from spraying with lights on, or turned back up soon after
 

Grojak

Well-Known Member
Here's a few for starters. Again I'm not saying one way or another. I'll do whatever keeps my plants healthy, but I did want to illustrate how confusing this place can be to navigate at times.





.991707/
First of all, why are you relying solely on this place for your info? If I responded every time I saw someone with 2 grows under their belt giving inaccurate info I’d have to quit me job. I’ve been reading published books since the 90’s when forums like this didn’t exist or I was too afraid to use them. I always say do your own research then come to a forum for clarification.

You can do or believe whatever you want to, there is no contradictions though. The old school theory of 6.3-6.5 for Veg and 6.1-6.3 for flower has never failed me with PM HP or PM Sunshine 4. If you can’t make it work with that then readeverything else I posted above.

good luck
 

RuggedWombat

Well-Known Member
First of all, why are you relying solely on this place for your info? If I responded every time I saw someone with 2 grows under their belt giving inaccurate info I’d have to quit me job. I’ve been reading published books since the 90’s when forums like this didn’t exist or I was too afraid to use them. I always say do your own research then come to a forum for clarification.

You can do or believe whatever you want to, there is no contradictions though. The old school theory of 6.3-6.5 for Veg and 6.1-6.3 for flower has never failed me with PM HP or PM Sunshine 4. If you can’t make it work with that then readeverything else I posted above.

good luck
Well I definitely dont solely rely on this forum, but I will say maybe I read the tea leaves more than I should sometimes. For example PThort says that PHing the water won't fix PH of the medium and it's actually carbonate and bicarbonate levels in the water that dictate the PH drift. Though I was aware of the water properties, the Internet overwhelmingly fixates purely on water PH which can also help explain why someone with 8 PH well water might have great success because they are lucky enough to have the right natural alkalinity to not fuck it up. I've also heard using a lot of PH down to try to get the PH in range can hurt the carbonate/bicarbonates in the water. Any insights on this? Foliage Pro has a ton of nitrate based N compared to ammonium or urea, combined with natural 7.8 PH water would that cause PH drift upwards over time regardless of feed PH? I suppose the test would be to measure the PH runoff over a period of time, probably with fresh waterings so the existing feed won't throw off the readings as much. My two focuses will be on feed strength and PH. Honestly even just cutting feed way back should right the helm at this point.


How did you settle on feed, feed, water? What's the frequency between waterings? I used to do feed, water, feed every 3 days for several years until it was suggested that my plants could get hungry during what is almost a 6 day period between feedings. I'm not overly concerned as I've recovered from far worse and it's all about challenging what we believe to be true to continue to improve. For shits and giggles, here's the results of my very first grow several years ago.
 

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LeastExpectedGrower

Well-Known Member
Well I definitely dont solely rely on this forum, but I will say maybe I read the tea leaves more than I should sometimes. For example PThort says that PHing the water won't fix PH of the medium and it's actually carbonate and bicarbonate levels in the water that dictate the PH drift. Though I was aware of the water properties, the Internet overwhelmingly fixates purely on water PH which can also help explain why someone with 8 PH well water might have great success because they are lucky enough to have the right natural alkalinity to not fuck it up. I've also heard using a lot of PH down to try to get the PH in range can hurt the carbonate/bicarbonates in the water. Any insights on this? Foliage Pro has a ton of nitrate based N compared to ammonium or urea, combined with natural 7.8 PH water would that cause PH drift upwards over time regardless of feed PH? I suppose the test would be to measure the PH runoff over a period of time, probably with fresh waterings so the existing feed won't throw off the readings as much. My two focuses will be on feed strength and PH. Honestly even just cutting feed way back should right the helm at this point.


How did you settle on feed, feed, water? What's the frequency between waterings? I used to do feed, water, feed every 3 days for several years until it was suggested that my plants could get hungry during what is almost a 6 day period between feedings. I'm not overly concerned as I've recovered from far worse and it's all about challenging what we believe to be true to continue to improve. For shits and giggles, here's the results of my very first grow several years ago.
I had been doing feed-water-water, and found my plants looked hungry starting somewhere in the water-water phase with an every 3 day (and even every 2nd day) schedule, so I moved that to feed-water-feed-water, etc. and still had a bit of yellowing. So I moved to feeding every time and making sure I had a good amount of runoff (I look for 25%). Last grow the plants with the same environmental conditions and inputs wanted every other day feeding...this time it's every two days rather than every other, but again never 'just water'. Much closer to a hydroponic setup.

My experience is that having high levels of calcium carbonates in water sounds great but isn't. I'm not sure that it's fully bioavailable to plants and when I didn't filter my water down, I often found I had calcium deficiencies and was way more prone to it locking out nitrogen and other nutrients. Natively my well water is ~.6EC/ 240-280PPM, pH 8+. I end up filtering it to 0 then adding back in calcium and magnesium (both as Cal/Mag and Epsom salts) in reasonable amounts. Since I did that it's been much easier to keep things on track. Now I use way more pH Up to 5.8pH, unless I'm using a drip system and have a reservoir running and need to knock it down a few tenths for a day or two.
 

RuggedWombat

Well-Known Member
I had been doing feed-water-water, and found my plants looked hungry starting somewhere in the water-water phase with an every 3 day (and even every 2nd day) schedule, so I moved that to feed-water-feed-water, etc. and still had a bit of yellowing. So I moved to feeding every time and making sure I had a good amount of runoff (I look for 25%). Last grow the plants with the same environmental conditions and inputs wanted every other day feeding...this time it's every two days rather than every other, but again never 'just water'. Much closer to a hydroponic setup.

My experience is that having high levels of calcium carbonates in water sounds great but isn't. I'm not sure that it's fully bioavailable to plants and when I didn't filter my water down, I often found I had calcium deficiencies and was way more prone to it locking out nitrogen and other nutrients. Natively my well water is ~.6EC/ 240-280PPM, pH 8+. I end up filtering it to 0 then adding back in calcium and magnesium (both as Cal/Mag and Epsom salts) in reasonable amounts. Since I did that it's been much easier to keep things on track. Now I use way more pH Up to 5.8pH, unless I'm using a drip system and have a reservoir running and need to knock it down a few tenths for a day or two.
Starting to get concerned the damage to the root zone might be hard to recover from. I barely fed them a couple of days ago and now they are looking fried again like I just dumped a ton more salts in. I'm giving them 2x the normal plain water as I have to get them back under control. At this point I may just do plain PHed water until the shit stops and the lower leaves start to yellow and drop. I evened measured the runoff PPM and PH and they don't seem that high so that makes me more concerned as I was expecting sky high PPM numbers from the salts being washed out. The plants dried out a day faster than normal so the middle one was drooping this morning which also doesnt help the salt situation. This was my first grow with feed every watering and doing too high PPM really fucked things up. I guess worst case scenario they make a good science experiment to learn from at this point, but it's irritating that I've done far worse and was able to recover so extra annoyed they apparently are choosing death. I mean I get it I made a poor call but whats it take to make these fuckers stop dying at this point like holy shit.

11/21 F5
3 gal water
6.3 PH
Lots of runoff to flush plants

11/24 F8
3 gal water
1/4 tsp PT per gallon
1/4 tsp FP per gallon
1/8 tsp MP per gallon
6 PH
370 PPM

11/27 F11
3 gal water
1/8 tsp PT per gallon
1/2 tsp FP per gallon
1/8 tsp per gallon
6.3 PH
830 PPM
Lots of runoff

11/30
6 gal water
6.0 PH
Plants dry. Middle one drooping. Water every 2 days
Runoff:
Plant 1: 5.6 PH 390 PPM
Plant 2: 5.8 PH 500 PPM
Plant 3: 5.6 PH 500 PPM
 

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LeastExpectedGrower

Well-Known Member
Starting to get concerned the damage to the root zone might be hard to recover from. I barely fed them a couple of days ago and now they are looking fried again like I just dumped a ton more salts in. I'm giving them 2x the normal plain water as I have to get them back under control. At this point I may just do plain PHed water until the shit stops and the lower leaves start to yellow and drop. I evened measured the runoff PPM and PH and they don't seem that high so that makes me more concerned as I was expecting sky high PPM numbers from the salts being washed out. The plants dried out a day faster than normal so the middle one was drooping this morning which also doesnt help the salt situation. This was my first grow with feed every watering and doing too high PPM really fucked things up. I guess worst case scenario they make a good science experiment to learn from at this point, but it's irritating that I've done far worse and was able to recover so extra annoyed they apparently are choosing death. I mean I get it I made a poor call but whats it take to make these fuckers stop dying at this point like holy shit.

11/21 F5
3 gal water
6.3 PH
Lots of runoff to flush plants

11/24 F8
3 gal water
1/4 tsp PT per gallon
1/4 tsp FP per gallon
1/8 tsp MP per gallon
6 PH
370 PPM

11/27 F11
3 gal water
1/8 tsp PT per gallon
1/2 tsp FP per gallon
1/8 tsp per gallon
6.3 PH
830 PPM
Lots of runoff

11/30
6 gal water
6.0 PH
Plants dry. Middle one drooping. Water every 2 days
Runoff:
Plant 1: 5.6 PH 390 PPM
Plant 2: 5.8 PH 500 PPM
Plant 3: 5.6 PH 500 PPM
What's the runoff on the days that you're only giving 3g of water? After 6g, I'd expect low EC/PPM because of all the water you've put through.

Remember that plants don't move as fast as we do, so don't expect them to show improvement in the window of a couple days when it comes to over-feeding, or lock outs, etc. It usually is a week or more to any kind of visible differences.

Also, different grow environments and different plants will impact how often you're watering. I don't love to wait until any plant starts drooping before I feed/water. It's better to gauge the soil dampness instead of thinking of a schedule.
 

RuggedWombat

Well-Known Member
What's the runoff on the days that you're only giving 3g of water? After 6g, I'd expect low EC/PPM because of all the water you've put through.

Remember that plants don't move as fast as we do, so don't expect them to show improvement in the window of a couple days when it comes to over-feeding, or lock outs, etc. It usually is a week or more to any kind of visible differences.

Also, different grow environments and different plants will impact how often you're watering. I don't love to wait until any plant starts drooping before I feed/water. It's better to gauge the soil dampness instead of thinking of a schedule.
Well honestly I haven't been checking runoff until the shit show started. I'm more interested in measuring PH drift, but the runoff PPM numbers can help to some extent. Those numbers are after the initial 3 gallons fyi. I had just pruned some of the fried leaves yesterday and they still felt pretty heavy so I was shocked to see one drooping this morning. That poor right plant is pretty fucked up though lol it was always the slowest to dry and it's just never gotten straightened out and is now obviously just starting to recover from the nutrient shock.
 

LeastExpectedGrower

Well-Known Member
Well honestly I haven't been checking runoff until the shit show started. I'm more interested in measuring PH drift, but the runoff PPM numbers can help to some extent. Those numbers are after the initial 3 gallons fyi. I had just pruned some of the fried leaves yesterday and they still felt pretty heavy so I was shocked to see one drooping this morning. That poor right plant is pretty fucked up though lol it was always the slowest to dry and it's just never gotten straightened out and is now obviously just starting to recover from the nutrient shock.
I generally don't bother with runoff pH or EC...unless there's a major problem. But when you're flushing, it's good to check the run off stats along the way, so you know how hot the medium had gotten as well as how effective your flush is and if you need to go further or have done enough. If you measured at 3g, it doesn't sound like your soil was all that hot if the plants were in the 390-500PPM range.
 

RuggedWombat

Well-Known Member
I generally don't bother with runoff pH or EC...unless there's a major problem. But when you're flushing, it's good to check the run off stats along the way, so you know how hot the medium had gotten as well as how effective your flush is and if you need to go further or have done enough. If you measured at 3g, it doesn't sound like your soil was all that hot if the plants were in the 390-500PPM range.
It's been about 4 hours now. Debating on letting them ride for 2 days or giving them a very light feeding of maybe 1/4 tsp of foliage pro. I'm hesitant as I still see leaf curl, especially on the right one. Better to have a light hand for the rest of the grow.
 
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