Ca problem?

[jER]

Hello Doc!
So one of my current 4 plants is sick, it was the one furthest ahead in flower when I had to leave town for 10 days for work. While I was away the plant began getting rusty coloured spots on the upper fan leaves. It also hasn't grown at all while its neighboor has shot up two feet in the same time period.
-Problem: rusty coloured spots on leaves
-Medium/grow method: rDWC
-Feed and supplements used: AN micro/grow/Bloom. Around 950ppm (.5)
-Water source: Tap (190ppm)
-Strain and age: Jack Herer Auto (80 days since sprout)
-Climate: 20-25deg C, 40% RH
- Light used: Mars 800W LED (365W draw)
-Additional info: plant has been showing symptoms for a couple weeks. While I was gone the TDS got pretty high (1300ppm) so I assumed that it was a lockout due to overfeeding, but I have since reduced the ppm and problem is still spreading a week later and second plant is starting to show the same symptoms. I have to go out of town again in a few days so I really need some advice on what is going wrong.

--Pictures

 

[Mañ'O'Green]

You do know that AN is designed to be run in water with a starting PPM < 50! 190 is pretty far out of range. This is the first thing you should fix. Dilute your tap water with RO or Di (distilled) water to get it in better range.

It looks like classic Ca deficiency and may have been triggered by high PPMs I see what also looks like a bit too much Nitrogen also from the high PPMs? but I think it may also be in part a PH problem. A lot of AN users do not watch PH close enough because well they are not supposed to have to. If PH is ok and PPMs after a res change are good then just wait to see if it stops spreading.

 

[namvet25]

I recommend removing some of those leaves that are covering your buds or tuck them out of the way so light reaches them.Also stop using grow nutes and use full strengh flower nutes to promote bud growth.

 

[davisgirl]

Yah, set that res to rights and it should take care of itself. I agree the leaves look a little thick, maybe a light defo. You got off lucky though, I’d leave for 10 days and come back to dead plants.

 

[jER]

I spoke to AN and they said my water should be ok to use. I got an analysis from the city and the ppm's are almost entirely Ca and Mg as it is Rocky Mountain water. I do do some pre-treatment to reduce bicarbonates, I bubble the water for a few days while adding phosphoric acid till the Ph stabilizes and stops rising back up. I do need to use a fair bit of acid which might be throwing off my P numbers, I am using around 0.20ml/L of AN's Ph down.

My Ph has been pretty stable at 5.9 to 6.0 so I don't think its a Ph issue. I had my wife taking measurements with a bluelab pen at least once a day.

I figured it was due to the high PPMs and figured that a rez change at a lower TDS would resolve the issue pretty quick, but now that I am seeing the same issue spreading on another plant a week after the rez change I got worried something else was up. Maybe the one plant that is much bigger than the others is drinking up all the available Ca?

I did try adding some GH calimagic, but everytime I have added that my airstones get completely plugged up by the next day and I have to replace them. Anyone else have this problem with calimagic?

I have been defoliating fairly regularily to try to keep some light on the smaller plants, those pictures were right after I had got back to town so they had got a little out of control.

As for the nutes @namvet25, AN's feed schedules show the same ratios throughout the grow although they add big bud during flower. I was thinking of switching to just the micro and 2x bloom instead of grow but I wasn't sure if that would upset the buffer system used to keep the Ph stable. Do you think I should switch to using just bloom? Or spend the ridiculous $ on big bud?

 

[namvet25]

I spoke to AN and they said my water should be ok to use. I got an analysis from the city and the ppm's are almost entirely Ca and Mg as it is Rocky Mountain water. I do do some pre-treatment to reduce bicarbonates, I bubble the water for a few days while adding phosphoric acid till the Ph stabilizes and stops rising back up. I do need to use a fair bit of acid which might be throwing off my P numbers, I am using around 0.20ml/L of AN's Ph down.

My Ph has been pretty stable at 5.9 to 6.0 so I don't think its a Ph issue. I had my wife taking measurements with a bluelab pen at least once a day.

I figured it was due to the high PPMs and figured that a rez change at a lower TDS would resolve the issue pretty quick, but now that I am seeing the same issue spreading on another plant a week after the rez change I got worried something else was up. Maybe the one plant that is much bigger than the others is drinking up all the available Ca?

I did try adding some GH calimagic, but everytime I have added that my airstones get completely plugged up by the next day and I have to replace them. Anyone else have this problem with calimagic?

I have been defoliating fairly regularily to try to keep some light on the smaller plants, those pictures were right after I had got back to town so they had got a little out of control.

As for the nutes @namvet25, AN's feed schedules show the same ratios throughout the grow although they add big bud during flower. I was thinking of switching to just the micro and 2x bloom instead of grow but I wasn't sure if that would upset the buffer system used to keep the Ph stable. Do you think I should switch to using just bloom? Or spend the ridiculous $ on big bud?

If AN says use grow then follow there directions

 

[davisgirl]

I spoke to AN and they said my water should be ok to use. I got an analysis from the city and the ppm's are almost entirely Ca and Mg as it is Rocky Mountain water. I do do some pre-treatment to reduce bicarbonates, I bubble the water for a few days while adding phosphoric acid till the Ph stabilizes and stops rising back up. I do need to use a fair bit of acid which might be throwing off my P numbers, I am using around 0.20ml/L of AN's Ph down.

My Ph has been pretty stable at 5.9 to 6.0 so I don't think its a Ph issue. I had my wife taking measurements with a bluelab pen at least once a day.

I figured it was due to the high PPMs and figured that a rez change at a lower TDS would resolve the issue pretty quick, but now that I am seeing the same issue spreading on another plant a week after the rez change I got worried something else was up. Maybe the one plant that is much bigger than the others is drinking up all the available Ca?

I did try adding some GH calimagic, but everytime I have added that my airstones get completely plugged up by the next day and I have to replace them. Anyone else have this problem with calimagic?

I have been defoliating fairly regularily to try to keep some light on the smaller plants, those pictures were right after I had got back to town so they had got a little out of control.

As for the nutes @namvet25, AN's feed schedules show the same ratios throughout the grow although they add big bud during flower. I was thinking of switching to just the micro and 2x bloom instead of grow but I wasn't sure if that would upset the buffer system used to keep the Ph stable. Do you think I should switch to using just bloom? Or spend the ridiculous $ on big bud?

How far in flower are your plants? Can we get some whole plant pics?

I’ve never used calimagic, but I haven’t heard of it doing that. Maybe just a bad bottle? In your situation, I would make a new res and follow AN feed schedule exactly, with their calmag and big bud.

 

[jER]

The 4 plants are currently all in flower, although they are all different in terms of maturity in flower. The one showing the most symptoms was and still is the furthest along in flower. I'd say they are probably in week 5 of flower? I am not sire how to say exactly when flowering "starts" for autos. Here is a pic from the front of the tent when I got back from my trip.

The sickest one is the small one on the right. The huge one on the left was about the same hight as the right one when I left and it grew 2' in 10 days. The right one didn't grow at all. My system re-circulates, so all 4 plants are esentially in the same water.

 

[jER]

Some more recent pics,
Here is the view from the front of the tent, big one on the left getting even bigger, sick one on the right still not gaining any height.

The sick one seems to be putting most of it energy into trying to produce new shoots around the bottom, but they are real scraggely and don't get nearly enough light. I have been picking these off here and there, but I don't want to stress the plant much more than I have too.

The buds on the main colas do seem to be building a bit of weight, but the pistles are already turning red.

 

[jER]

I spoke to the owner of one of the local hydro shops and he was certain that it looked like rust fungus not deficiency. I don't know if I agree with him though, I don't see anything that looks like spores on the underside of the leaf and nothing rubs off when I rub them. Anyone here have experience with rust fungus? I don't want to spray my flowering plants if I don't absolutely need to