First time here on forum. 3rd crop cycle grower. I'm a detail oriented guy so I hope this isn't too much information for most of you. 
I suspect I have an iron deficiency in my plants and have been trying to fix it over past several weeks with no luck.
Grow Room
Size: 4x3x4
Lights: 11 on/ 13 off
2x 300w Viparspectra LED and 1x 600w Viparspectra LED - all running on full veg/bloom (Heights - 11" and 17" respectively)
750-800 μmoles at center under each light. Perimeter of room reading around 250-350 μmoles.
(Using Hydrofarm Quantum Light Meter -- I'm not entirely sure of it's accuracy however.)
Temps: Day and Night 75-81 avrg.
Humidity: 48-60%
Growing medium - coco-coir
Fertizlizer
GH Botanicals - Using Transition mix schedule currently
Micro - 2.5 ml/gal
Grow - 2.5 ml/gal
Bloom - 2.5 ml/gal
CalMAg - 2.5 ml/gal
Water is town aquifer and is not chlorinated.
Water and Fert ph'd to ~4.5 -5.0
Runoff ph ~6.0
(Using GH pH Indicator solution)
**Runoff ph has been running in the 6.5 range for much of the grow and I have been working to lower it. I did one heavy flush maybe 10 days ago. It has been moving slowly downward.
I have been alternating between watering and fertilizing with about 10% runoff for each.
Other Growing Info:
Have been exchanging air in room less than normal since I'm heating the room (heater in room) and trying to keep heating costs down a little. One 3.5" comp fan running at 50% speed. I've moved it to full speed yesterday thinking maybe plants are suffering from trying to grow hard in too little CO2. In the past I have run 2 comp fans for exhaust for heat control in summer, but each one is rated for 38 CFM so i expect one should be more than needed for exchange I think. Room has several comp. fans in it circulating air.
The I switched the cycle about 10 days ago (they were showing the symptoms before the switch) about 10 days ago or so and I think they are behind in showing flowers based on my previous grows.
Here are my recent grow records if that is helpful.
The Plants' symptoms:
Yesterday I watered them (No nutes save for CalMag) and today the symptoms are as bad as I have seen! Yikes!
New leaves and growing tips are fairly pale with the growing tips starting out almost white a some points. The yellowing starts near the base of the leaves and tapers as it moves outward, with the yellowing being being between the veins and ribs. The amount of yellowing has varied a little and seems to be reduced after I fertilize but starts to increase again, especially after a water day. The yellowing shows on all the growing shoots, even those lower in the canopy -- i.e. not under the strongest light amounts. As the leaves mature the color goes full green.
The AK 47 shows the most general pale color and that plant seems to want more nutes than the other varieties, but I haven't given it a different fert sched yet. I was waiting until I get a handle on the problem for all the plants first. (I had some trouble with the AK 47 in my last grow as well (different symptoms) so I think it's a bit more finicky than the other plants. I'm now beginning to think of it as my canary in the coal mine for problems.)
The White Widow auto seems to be doing fine but I think the buds are developing too slowly.
What I've been trying:
I originally thought it might be light burn and I lowered the light levels quite a bit (put 600w on bloom only and lower 300w veg amount and raised lights - intensity was around 400 μmoles in the center and only 200 at the edges.) The symptoms got a little better but the plants were stretching quite a bit from the lower light levels (more than I expected from just the light cycle change) and I no longer think it was light stress. I now think it is an iron deficiency. I suspect that under stronger lighting, the plants are growing faster and so the iron deficiency becomes a bigger problem then.
I have been adding more Micro in the water only days since it has iron but then I discovered that the CalMag has iron in it as well without as much N so I have been adding that to water days now only. I usually add some to the water only days but not always at 2.5 ml/gal. Now I'm going full 2.5 ml/gal.
I am just now wondering if I am not giving them enough nutes in general. I have been using this schedule which I think I found on GWE but I might have found it on another site?
Looking around the forum I found this schedule which is a heavier nute loading (I'm feeding at less than the 1/4 str. on this chart!!)
This chart was from a DWC grow, but coco is supposed to be closer to hydro in nute needs I believe.
Last night in desperation I tried giving them a little CalMag foliar feeding - .2ml / pint and misted them heavily, but not dripping.
I have grown under the first chart above and my previous crop (exactly same plants - both crops from seed) did fine and even had a little nute burn at times. But that was during a different season (summer) so temps and humidity were different then. I figured that with my lowish humidity (it was in the 35% range at the start of the grow) I should expect nut burn since they go through water pretty quickly, but I haven't seen any burning at this point. I'm wondering if I should really up my nutes. I'm going to try fertilize 2x and then water. Should I go higher in my nutes?
Everything I read says they should have enough iron just from tap water and more than enough from the fert. I have suspected some lock out from too high pH for a coco grow and I've been trying to lower the pH for several weeks now. But the runoff is at 6.0 or so, so I think that should be in the o.k. range right? I've also read that an iron deficiency can stunt bud development so I have thought iron might be the problem with the buds not really forming yet -- though I acknowledge it's still a little early after the cycle change.
Looking for any help.
I suspect I have an iron deficiency in my plants and have been trying to fix it over past several weeks with no luck.
Grow Room
Size: 4x3x4
Lights: 11 on/ 13 off
2x 300w Viparspectra LED and 1x 600w Viparspectra LED - all running on full veg/bloom (Heights - 11" and 17" respectively)
750-800 μmoles at center under each light. Perimeter of room reading around 250-350 μmoles.
(Using Hydrofarm Quantum Light Meter -- I'm not entirely sure of it's accuracy however.)
Temps: Day and Night 75-81 avrg.
Humidity: 48-60%
Growing medium - coco-coir
Fertizlizer
GH Botanicals - Using Transition mix schedule currently
Micro - 2.5 ml/gal
Grow - 2.5 ml/gal
Bloom - 2.5 ml/gal
CalMAg - 2.5 ml/gal
Water is town aquifer and is not chlorinated.
Water and Fert ph'd to ~4.5 -5.0
Runoff ph ~6.0
(Using GH pH Indicator solution)
**Runoff ph has been running in the 6.5 range for much of the grow and I have been working to lower it. I did one heavy flush maybe 10 days ago. It has been moving slowly downward.
I have been alternating between watering and fertilizing with about 10% runoff for each.
Other Growing Info:
Have been exchanging air in room less than normal since I'm heating the room (heater in room) and trying to keep heating costs down a little.
One 3.5" comp fan running at 50% speed. I've moved it to full speed yesterday thinking maybe plants are suffering from trying to grow hard in too little CO2. In the past I have run 2 comp fans for exhaust for heat control in summer, but each one is rated for 38 CFM so i expect one should be more than needed for exchange I think. Room has several comp. fans in it circulating air.The I switched the cycle about 10 days ago (they were showing the symptoms before the switch) about 10 days ago or so and I think they are behind in showing flowers based on my previous grows.
Here are my recent grow records if that is helpful.
The Plants' symptoms:
Yesterday I watered them (No nutes save for CalMag) and today the symptoms are as bad as I have seen! Yikes!
New leaves and growing tips are fairly pale with the growing tips starting out almost white a some points. The yellowing starts near the base of the leaves and tapers as it moves outward, with the yellowing being being between the veins and ribs. The amount of yellowing has varied a little and seems to be reduced after I fertilize but starts to increase again, especially after a water day. The yellowing shows on all the growing shoots, even those lower in the canopy -- i.e. not under the strongest light amounts. As the leaves mature the color goes full green.
The AK 47 shows the most general pale color and that plant seems to want more nutes than the other varieties, but I haven't given it a different fert sched yet. I was waiting until I get a handle on the problem for all the plants first. (I had some trouble with the AK 47 in my last grow as well (different symptoms) so I think it's a bit more finicky than the other plants. I'm now beginning to think of it as my canary in the coal mine for problems.)
The White Widow auto seems to be doing fine but I think the buds are developing too slowly.
What I've been trying:
I originally thought it might be light burn and I lowered the light levels quite a bit (put 600w on bloom only and lower 300w veg amount and raised lights - intensity was around 400 μmoles in the center and only 200 at the edges.) The symptoms got a little better but the plants were stretching quite a bit from the lower light levels (more than I expected from just the light cycle change) and I no longer think it was light stress. I now think it is an iron deficiency. I suspect that under stronger lighting, the plants are growing faster and so the iron deficiency becomes a bigger problem then.
I have been adding more Micro in the water only days since it has iron but then I discovered that the CalMag has iron in it as well without as much N so I have been adding that to water days now only. I usually add some to the water only days but not always at 2.5 ml/gal. Now I'm going full 2.5 ml/gal.
I am just now wondering if I am not giving them enough nutes in general. I have been using this schedule which I think I found on GWE but I might have found it on another site?
Looking around the forum I found this schedule which is a heavier nute loading (I'm feeding at less than the 1/4 str. on this chart!!)
This chart was from a DWC grow, but coco is supposed to be closer to hydro in nute needs I believe.
Last night in desperation I tried giving them a little CalMag foliar feeding - .2ml / pint and misted them heavily, but not dripping.
I have grown under the first chart above and my previous crop (exactly same plants - both crops from seed) did fine and even had a little nute burn at times. But that was during a different season (summer) so temps and humidity were different then. I figured that with my lowish humidity (it was in the 35% range at the start of the grow) I should expect nut burn since they go through water pretty quickly, but I haven't seen any burning at this point. I'm wondering if I should really up my nutes. I'm going to try fertilize 2x and then water. Should I go higher in my nutes?
Everything I read says they should have enough iron just from tap water and more than enough from the fert. I have suspected some lock out from too high pH for a coco grow and I've been trying to lower the pH for several weeks now. But the runoff is at 6.0 or so, so I think that should be in the o.k. range right? I've also read that an iron deficiency can stunt bud development so I have thought iron might be the problem with the buds not really forming yet -- though I acknowledge it's still a little early after the cycle change.
Looking for any help.
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