DataDriven
- 1
- 3
Sincerely appreciate anyone that will help! I am lost on this one...
Background
I have a basement grow that I recently took over. The room was set up with 1000W MH lights (Running @ 750W), CO2 capable, and 6" (Hugo) Rockwool as medium. I use RO water. I was given 2 portable "large" home humidifiers (surprisingly, pint rating not available) and a commercial grade dehumidifier @ 200 PPD.
General Info.. I follow VPD guidlines and am currently in week 5 of Veg. Light intensity range relative to the top of the canopy is anywhere between 400-650 umol over any one plant. I have been hand feeding once the rockwool is virtually dry (roughly 5%-15% saturation) during veg for root establishment before going to feeding at 50% saturation (have not started feeding at 50% saturation, plan was to start this week). PPM has never reached over 750PPM for any one feed and before this issue, plants were a consistent nice medium green color. I would feed until 10-20% runoff was achieved. Runoff PPM was never over 100PPM above or below feed PPM. I have consistently fed at 5.8 PH with the temperature of feed at 68 degrees. PH runoff was always 5.8 during this time. Before the issue, VPD was consistently between 0.9-1.2 kPa. Also, nutrient mix in container has remained fairly constant with PH and PPM.. typically slight increase in PH by .1 The plants were very healthy and growing at this point with great leaf posture.
When Issue Started
During week 3, I started to have a humidity issue. The weather became really dry outside and although the room is pretty well sealed, I could not generate enough humidity to get back to proper VPD. Humidity dipped to 30%-35% for several days and kPa went to 21.8. Even after adding 1 - 200 pint per day humidifier, it wasn't until I added a second 200 pint humidifier until I was able to get the humidity back up to 65-70%. The leaves started to show several signs of deficiencies and I am aware the plant will only take up water during humidity droughts and potentially leave nutrient salts behind locking out the plant of proper nutrition. Once I was able to get the humidity back up, I started to see my PH runoff drop. I feed each plant as needed so as the first few plants required feeding, runoff was measured at 5.3 PH, following day (as other plants were ready to feed) 5.0, then below 5 the next day.
Something to mention, but to my knowledge shouldn't have much of an impact, is I started running CO2 from 600-800 PPM before the humidity drop. I've read this can increase humidity... didn't help FWIW. :)
Thinking I had a nutrient build up issue, due to the plant only taking up water during the low humidity time, this was the catalyst for creating the toxic low PH issue, I performed a flush with RO water and Clearex. 2 days later, as the one of the plants was roughly @ 50% saturation, I wanted to see if the runoff was still drastically lower than the feed PH. I feed with a PH @ 5.9 and runoff was still low at 4.9!
Other important info.. Roots are abundant. They look and smell healthy so I do not believe I have root rot (pics attached).
Any help would be greatly appreciated!!
Background
I have a basement grow that I recently took over. The room was set up with 1000W MH lights (Running @ 750W), CO2 capable, and 6" (Hugo) Rockwool as medium. I use RO water. I was given 2 portable "large" home humidifiers (surprisingly, pint rating not available) and a commercial grade dehumidifier @ 200 PPD.
General Info.. I follow VPD guidlines and am currently in week 5 of Veg. Light intensity range relative to the top of the canopy is anywhere between 400-650 umol over any one plant. I have been hand feeding once the rockwool is virtually dry (roughly 5%-15% saturation) during veg for root establishment before going to feeding at 50% saturation (have not started feeding at 50% saturation, plan was to start this week). PPM has never reached over 750PPM for any one feed and before this issue, plants were a consistent nice medium green color. I would feed until 10-20% runoff was achieved. Runoff PPM was never over 100PPM above or below feed PPM. I have consistently fed at 5.8 PH with the temperature of feed at 68 degrees. PH runoff was always 5.8 during this time. Before the issue, VPD was consistently between 0.9-1.2 kPa. Also, nutrient mix in container has remained fairly constant with PH and PPM.. typically slight increase in PH by .1 The plants were very healthy and growing at this point with great leaf posture.
When Issue Started
During week 3, I started to have a humidity issue. The weather became really dry outside and although the room is pretty well sealed, I could not generate enough humidity to get back to proper VPD. Humidity dipped to 30%-35% for several days and kPa went to 21.8. Even after adding 1 - 200 pint per day humidifier, it wasn't until I added a second 200 pint humidifier until I was able to get the humidity back up to 65-70%. The leaves started to show several signs of deficiencies and I am aware the plant will only take up water during humidity droughts and potentially leave nutrient salts behind locking out the plant of proper nutrition. Once I was able to get the humidity back up, I started to see my PH runoff drop. I feed each plant as needed so as the first few plants required feeding, runoff was measured at 5.3 PH, following day (as other plants were ready to feed) 5.0, then below 5 the next day.
Something to mention, but to my knowledge shouldn't have much of an impact, is I started running CO2 from 600-800 PPM before the humidity drop. I've read this can increase humidity... didn't help FWIW. :)
Thinking I had a nutrient build up issue, due to the plant only taking up water during the low humidity time, this was the catalyst for creating the toxic low PH issue, I performed a flush with RO water and Clearex. 2 days later, as the one of the plants was roughly @ 50% saturation, I wanted to see if the runoff was still drastically lower than the feed PH. I feed with a PH @ 5.9 and runoff was still low at 4.9!
Other important info.. Roots are abundant. They look and smell healthy so I do not believe I have root rot (pics attached).
Any help would be greatly appreciated!!
