Lack of Oxygen or Nutrient Excess on seedling?

oregonhydro · Oct 22, 2020

Hello all,

I've recently begun my first grow, a DWC/bubbleponics setup, 4 plants in 2 20gal totes.

I'd made a post about this grow already as I was having big temperature worries. Babies seem to be happy keeping them below 85, & giving a small amount of silica ( i have been keeping track of pH and adjusting up to 2x a day, always lowering it. Raises from 5.8 to 6.3 during the day and I bring it back down) . It's getting colder outside so that should help.

I was dumb and made a horrible mistake I will never again make, I left the pumps off for around 5hrs. No water for the babies, just when they were hitting their 1st week from sprout. All 4 plants were limp when i got back, but I supported them up until they regained their strength. The weakest didn't make it, so now I'll have to get a clone to replace her. I'm just over 2 weeks in now and plants seem to be growing well, just saw roots finally poking out of the 6" net pot this morning, looking bright white!

My only problem is this one plant, which was performing the best at first!. I had her and her sister in one tote, the same ~450ppm solution.
She started to have leaf curl on my most recent res change two days ago, but her sister was fine so I thought it was too much wind. Even with indirect airflow for 24hr only got worse, I gave her a rinse with 5.5 150ppm water. I get my water from the tap with a garden hose filter, comes around 7.4 pH, takes 2ml/ Gal ph down to lower it enough.
She has started to curl worse and developed slide edge burning and brown blistering. Moved her to the other rez in the spot of the seedling I killed, only 250ppm res . She has perked up a bit since, I think shell recover but her sister (from seed though) is still doing well in the higher ppm solution.

What could the problem have been? I have airstones and drip irrigation to the top, which should create space for oxygen on it's own. She was handling nutes well up to this point as I had her at around 400ppm from 3 days old. Everything is sterile with h202 and water temps dont get above 80 ( I use ice packs )

1st picture w/hdroton when drooping was worst, 2nd is how she looks now & 3rd is her sister.

and yes.. gorilla tape holding irrigation in place :rolleyes:

rkymtnman · Oct 22, 2020

oregonhydro said:
the same ~450ppm

that seems really, really high. i don't see any tip burn yet.

Distortionist · Oct 24, 2020

I agree food seems way too high, my PPM on full blown flowering plants never exceeded 850 or 900. I usually aim for 750 really, over 900 gave me tip burn. for plants that small I think 300 would be more than enough I think. Check the roots on the curly plant, they have have gotten weak and infected with fungus. That is how my root rot started, clogged dripper, a bit of heat, and i was fighting root rot for months.

oregonhydro · Oct 25, 2020

rkymtnman said:
that seems really, really high. i don't see any tip burn yet.

Distortionist said:
I agree food seems way too high, my PPM on full blown flowering plants never exceeded 850 or 900. I usually aim for 750 really, over 900 gave me tip burn. for plants that small I think 300 would be more than enough I think. Check the roots on the curly plant, they have have gotten weak and infected with fungus. That is how my root rot started, clogged dripper, a bit of heat, and i was fighting root rot for months.

I was under the impression full flowering plants could stand up to 1800 PPM. Whoops. At least looking at my botanicare KIND nutes, the ppm would be at least 1500 if I followed the charts recommended ml/gal during flower. I'll try to err closer to the side of deficiency in the future, but right now I'm at ~500ppm 5.8pH 75°F water with with a little silica and 12% h202 2ml/4L. Plants shown in picture are one seemingly loving it, and her sister having a hard time. Same seeds. ~ 450 ppm doing well for another plant as well.

Thanks for the advice... Stems are starting to thicken up quite a bit, don't see too much stretch 600w cooled mh now ~2.5ft away. Could they have been growing even faster, if I fed them less nutrients?

Distortionist · Oct 26, 2020

oregonhydro said:
I was under the impression full flowering plants could stand up to 1800 PPM. Whoops. At least looking at my botanicare KIND nutes, the ppm would be at least 1500 if I followed the charts recommended ml/gal during flower. I'll try to err closer to the side of deficiency in the future, but right now I'm at ~500ppm 5.8pH 75°F water with with a little silica and 12% h202 2ml/4L. Plants shown in picture are one seemingly loving it, and her sister having a hard time. Same seeds. ~ 450 ppm doing well for another plant as well.

Thanks for the advice... Stems are starting to thicken up quite a bit, don't see too much stretch 600w cooled mh now ~2.5ft away. Could they have been growing even faster, if I fed them less nutrients?

Yeah I've heard of people feeding slightly over 1000 but not 1800! It also depends on the plant and food, I don't really see too many people here feeding above 1000 here at all but I think 1200 is the highest I've seen.

bonytang · Oct 28, 2020

oregonhydro said:
Hello all,

I've recently begun my first grow, a DWC/bubbleponics setup, 4 plants in 2 20gal totes.

I'd made a post about this grow already as I was having big temperature worries. Babies seem to be happy keeping them below 85, & giving a small amount of silica ( i have been keeping track of pH and adjusting up to 2x a day, always lowering it. Raises from 5.8 to 6.3 during the day and I bring it back down) . It's getting colder outside so that should help.

I was dumb and made a horrible mistake I will never again make, I left the pumps off for around 5hrs. No water for the babies, just when they were hitting their 1st week from sprout. All 4 plants were limp when i got back, but I supported them up until they regained their strength. The weakest didn't make it, so now I'll have to get a clone to replace her. I'm just over 2 weeks in now and plants seem to be growing well, just saw roots finally poking out of the 6" net pot this morning, looking bright white!

My only problem is this one plant, which was performing the best at first!. I had her and her sister in one tote, the same ~450ppm solution.
She started to have leaf curl on my most recent res change two days ago, but her sister was fine so I thought it was too much wind. Even with indirect airflow for 24hr only got worse, I gave her a rinse with 5.5 150ppm water. I get my water from the tap with a garden hose filter, comes around 7.4 pH, takes 2ml/ Gal ph down to lower it enough.
She has started to curl worse and developed slide edge burning and brown blistering. Moved her to the other rez in the spot of the seedling I killed, only 250ppm res . She has perked up a bit since, I think shell recover but her sister (from seed though) is still doing well in the higher ppm solution.

What could the problem have been? I have airstones and drip irrigation to the top, which should create space for oxygen on it's own. She was handling nutes well up to this point as I had her at around 400ppm from 3 days old. Everything is sterile with h202 and water temps dont get above 80 ( I use ice packs )

1st picture w/hdroton when drooping was worst, 2nd is how she looks now & 3rd is her sister.

and yes.. gorilla tape holding irrigation in place

Great start, 85 is excessively high for dwc though for sure winter will help your res stay cool..for now 85/warm temps are "ok" for seedlings but once they hit 2 nodes up they'll be struggling if temps get above 75. At most 72 is a good aiming point. Not sure how big your ice packs are but usually a frozen 2liter bottle will be perfect for a day.

In your 1st pic it looks like a fresh top feed but if you see the lower leaves starting to bleach up while curling it's stomata likely from high humidity. It happens especially with small clones, or when leaves too close to the grow media. On the feed some like to run nutes on the dosing chart or at 1/2 strength but really for now I like to run at less than 1/2 for little plants. Every plant will feed differently so PPM's really need to be on the lower side to prevent lock out, + always easier to feed more later. If you can run low nutes then work up to full feed levels that's always best. They're suffocating now with high temps so reallu feed as low as possible till temps become more manageable.

Lack of Oxygen or Nutrient Excess on seedling?

oregonhydro

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rkymtnman

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Distortionist

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oregonhydro

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Distortionist

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bonytang

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