Delps8
Well-Known Member
I'm having some nute issues and I'd appreciate some feedback on what's causing it and potential remedies.
The symptoms are that a few of the leaves at the top of the canopy on two stems from one plant ("Alice") and one leaf at the top of the canopy on the other plant ("Annie") have suddenly developed a few light spots on the leaves, numerous dark tan/light grown spots in a handful of leaves, and those leaves and a few others have leaf tips that are slightly curled.
Alice was slow out of the gate during germination, is noticeably smaller than Annie, and, during veg, was not able to handle as much light as Annie.
The plants were vegged using a Growcraft X2 veg light and the amount of foliage is significant. All foliage is strong and solid green. The only other issue that I've seen in the foliage has been from nutrient water falling on the leaves in early veg. Interestingly, those leaves are still visible and the damaged areas have neither overgrown or deteriorated.
I've removed dead and dying fan leaves and poorly developed branches from the under carriage.
First symptoms were two days ago, when I first saw that some of the leaf tips were slightly curled but the discoloration has manifested in the last 36 hours.
I've checked the symptoms against the standard symptoms charts and the only thing that looks like it might be the culprit is magnesium but that's a mobile chemical that would impact lower leaves. Given that this is occurring on new growth could it be calcium or magnesium?
The details on the grow are here. I haven't posted much about this grow in the grow journal so the details on this issue are here:
Two Strawberry Pie autos in flower, 56 days since germination.
Light-PPFD and DLI data at the end of the posting. I've dropped DLI a bit over the past few days. Some spots have had PPFD's in the low to mid 900's but the average value for the top of the canopy has had a DLI's in the high 50's and low 60's. Photoperiod is 20/4. Lights are out from 1630 to 2030 - that cuts my cost per KwH from 61¢ to 34¢ and drops my lighting cost from $110± to $65±. Gotta love California.
Temperature-very stable with lows in the mid 70's during lights out and highs in the low 80's.
Humidity-not as stable as I'd like because the grow is in an unheated garage in SoCal. The past few days have been lows at 60°± and highs in the mid-70's.
Wind-AC Infinity fan blowing at 1/10 over the canopy.
CO2-ambient.
Root zone temperature-water chiller keeps the res at 68°
Water - RO water at 0 PPM. Water uptake has been 1 to 1.5 gallons per day.
Nutrients - Jack's 3-2-1 mixed at the current recommended mixture of 3.79-2.52-0.99 gm/gallon.
Reservoir is new as of 10/22/22 at 860/550 PPM//EC 1.72. Due to water uptake and topping up, PPM is 820/500//EC 1.64. Over the course of the past two days, PPM has fluctuated between 810/500 and 820/500.
pH has been as expected. Over the past three grows, when I swap the res, pH drops very slowly for two or three days and is then stable. In this res, pH dropped for two days.
Unlike previous grows (2 Gorilla Glue grows and 1 Gelato, all autos), I have seen this res exhibit the "EC dropping, pH rising" behavior that hydro grows typically exhibit. The previous res started at 790/500 but PPM dropped over the course of the week and it was 590 PPM when I swapped the res.
Oxygen-no changes since I started growing. Using BubbleMac airstones are were sterilized at the start of the grow and were functioning as expected when checked during the last res swap.
Roots-pure white with fresh dirt smell when checked during the last res swap.
Light Data
The symptoms are that a few of the leaves at the top of the canopy on two stems from one plant ("Alice") and one leaf at the top of the canopy on the other plant ("Annie") have suddenly developed a few light spots on the leaves, numerous dark tan/light grown spots in a handful of leaves, and those leaves and a few others have leaf tips that are slightly curled.
Alice was slow out of the gate during germination, is noticeably smaller than Annie, and, during veg, was not able to handle as much light as Annie.
The plants were vegged using a Growcraft X2 veg light and the amount of foliage is significant. All foliage is strong and solid green. The only other issue that I've seen in the foliage has been from nutrient water falling on the leaves in early veg. Interestingly, those leaves are still visible and the damaged areas have neither overgrown or deteriorated.
I've removed dead and dying fan leaves and poorly developed branches from the under carriage.
First symptoms were two days ago, when I first saw that some of the leaf tips were slightly curled but the discoloration has manifested in the last 36 hours.
I've checked the symptoms against the standard symptoms charts and the only thing that looks like it might be the culprit is magnesium but that's a mobile chemical that would impact lower leaves. Given that this is occurring on new growth could it be calcium or magnesium?
The details on the grow are here. I haven't posted much about this grow in the grow journal so the details on this issue are here:
Two Strawberry Pie autos in flower, 56 days since germination.
Light-PPFD and DLI data at the end of the posting. I've dropped DLI a bit over the past few days. Some spots have had PPFD's in the low to mid 900's but the average value for the top of the canopy has had a DLI's in the high 50's and low 60's. Photoperiod is 20/4. Lights are out from 1630 to 2030 - that cuts my cost per KwH from 61¢ to 34¢ and drops my lighting cost from $110± to $65±. Gotta love California.
Temperature-very stable with lows in the mid 70's during lights out and highs in the low 80's.
Humidity-not as stable as I'd like because the grow is in an unheated garage in SoCal. The past few days have been lows at 60°± and highs in the mid-70's.
Wind-AC Infinity fan blowing at 1/10 over the canopy.
CO2-ambient.
Root zone temperature-water chiller keeps the res at 68°
Water - RO water at 0 PPM. Water uptake has been 1 to 1.5 gallons per day.
Nutrients - Jack's 3-2-1 mixed at the current recommended mixture of 3.79-2.52-0.99 gm/gallon.
Reservoir is new as of 10/22/22 at 860/550 PPM//EC 1.72. Due to water uptake and topping up, PPM is 820/500//EC 1.64. Over the course of the past two days, PPM has fluctuated between 810/500 and 820/500.
pH has been as expected. Over the past three grows, when I swap the res, pH drops very slowly for two or three days and is then stable. In this res, pH dropped for two days.
Unlike previous grows (2 Gorilla Glue grows and 1 Gelato, all autos), I have seen this res exhibit the "EC dropping, pH rising" behavior that hydro grows typically exhibit. The previous res started at 790/500 but PPM dropped over the course of the week and it was 590 PPM when I swapped the res.
Oxygen-no changes since I started growing. Using BubbleMac airstones are were sterilized at the start of the grow and were functioning as expected when checked during the last res swap.
Roots-pure white with fresh dirt smell when checked during the last res swap.
Light Data
