Need help with this little problem... 2nd grow same problem.

F

Frankfrank

Member
Hi
I need a little help correcting the problem I have. From what I've seen on the web my problem might be a light problem but I would like to get some help to confirm this.

Strain : Bubblegum
Medium: Hydroton
Stage of growth: end of 3rd week flowering ( Clones were veged for 4 days then straight to flower)
Watering: 4 times a day for 15min.
Lights: 2x 1200W LED Flowering spectrum with 4' growlux T8 on the sides
Temps are kept between 74 - 82F

Using H&G full line.

Its my 2nd run with this setup and strain. Im getting the same problem as with the previous grow.

The thing that bothers me is that its not only yellowing of leaves but brown necrotic spots appear on leaves as well.IMGP0005a.jpg
IMGP0009a.jpg



The weird thing is that the plants on the 2nd half of the table all doing much better but they are all grown in the same setup ( same light, same reservoir ...)

The only difference would be they are 3/4" lower because of the slope on the table.

IMGP0011a.jpg


Thx
 

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Last edited:
MammothGrow

MammothGrow

Well-Known Member
Frankfrank said:
Hi
I need a little help correcting the problem I have. From what I've seen on the web my problem might be a light problem but I would like to get some help to confirm this.

Strain : Bubblegum
Medium: Hydroton
Stage of growth: end of 3rd week flowering ( Clones were veged for 4 days then straight to flower)
Watering: 4 times a day for 15min.
Lights: 2x 1200W LED Flowering spectrum with 4' growlux T8 on the sides
Temps are kept between 74 - 82F

Using H&G full line.

Its my 2nd run with this setup and strain. Im getting the same problem as with the previous grow.

The thing that bothers me is that its not only yellowing of leaves but brown necrotic spots appear on leaves as well.View attachment 3293494
View attachment 3293495



The weird thing is that the plants on the 2nd half of the table all doing much better but they are all grown in the same setup ( same light, same reservoir ...)

The only difference would be they are 3/4" lower because of the slope on the table.

View attachment 3293502


Thx
Click to expand...
First off whats your ph at?? You definitely have a Magnesium deficiency there, and probably lacking calcium as well. Are you using RO water? and are you adding cal/mag to it?
 
F

Frankfrank

Member
I let ph drift between 5.5 and 6.2 gradually. Never adjusting for more than .3 at a time.

If its a defiency why is it mainly under the center of the Led panels??

Its really like a round yellow spot in the middle of the half of my flood table. Thats why i tought the light might be the prob.

Lights are kept at min 12" from top...

I added calmag at 2nd week at a rate of 5ml/gal.

Im using tap water.
Tap ppm is at 114.
 
MammothGrow

MammothGrow

Well-Known Member
Frankfrank said:
I let ph drift between 5.5 and 6.2 gradually. Never adjusting for more than .3 at a time.

If its a defiency why is it mainly under the center of the Led panels??

Its really like a round yellow spot in the middle of the half of my flood table. Thats why i tought the light might be the prob.

Lights are kept at min 12" from top...

I added calmag at 2nd week at a rate of 5ml/gal.

Im using tap water.
Tap ppm is at 114.
Click to expand...
How many gallons of water in your reservoir and how much of each of your nutrients do you have in there? And how often do you change the res out. Its hard to tell, I see a couple leaves near the bottom that look like a P deficiency, also a leaf in there that looks K deficiency. the close up shot of the one leaf looks like a ph imbalance but also looks like it could be excess salt buildup. so are you sure you've fed them enough? ph is right, you've flushed them so no slat buildup? whats your runoff EC? etc.
 
F

Frankfrank

Member
Res is 50gal changed religiously every 7 days.
Airstones in the res...

Im following h&g calculator.
Ppm is around 850

I use aquaflakes a&b

Drip clean

Amino treatment(last week)

Root excel ( last week as well)

Cannazym instead of multizen.

I only flush at the end as prescribed by h&g.

I recalibrate my ph meter every 2 weeks.

Sorry to bring this back again but the problem affects only an area of the table. The one thats right under the light. That why i tought my prpblem might be light related.

If the problem was a defiency it would affect every plant in the same way no mater whre the plant is in the table no??

Other thing. I only top up when necessary with plain water...
 
A

AnonymousPatriot420

Member
ppm is only at 850? that seems low for 3-4 weeks in flowering imo.

does your led light have a few uvb led's in the middle? might be that if so since it is localized under the led. i highly doubt it, but just a thought.
 
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F

Frankfrank

Member
Following house and garden charts gives a ppm of around 1100 at week 6.
Canadian website states target ppms...

As for the uvb i dont know. Will ask reseller but as far as i know its only red spectrum, Thats why i add grolux t8 on the sides.

Both lamps are the same but ordered 6 months appart. The color of the light they give off is not exactly the same bit pretty close. One is redder the other one whiter.
 
A

AnonymousPatriot420

Member
if it were me i wold try kicking up the ppm to 1000-1100 and use 10ml of calmag per gallon as that is the "heavy dose"

the plants are growing at a high rate at this stage and need lots of nutes to make those sweet buds. :)
 
MammothGrow

MammothGrow

Well-Known Member
Frankfrank said:
Res is 50gal changed religiously every 7 days.
Airstones in the res...

Im following h&g calculator.
Ppm is around 850

I use aquaflakes a&b

Drip clean

Amino treatment(last week)

Root excel ( last week as well)

Cannazym instead of multizen.

I only flush at the end as prescribed by h&g.

I recalibrate my ph meter every 2 weeks.

Sorry to bring this back again but the problem affects only an area of the table. The one thats right under the light. That why i tought my prpblem might be light related.

If the problem was a defiency it would affect every plant in the same way no mater whre the plant is in the table no??

Other thing. I only top up when necessary with plain water...
Click to expand...
If its only happening where the light is most intense then it could be not enough food for them
 
F

Frankfrank

Member
Changing water tomorrow will try kicking up the ppm.

Do you guys top up with plain or nuted water? There seem to be different opinions on this one.
 
Flagg420

Flagg420

Well-Known Member
Depends on the readings, they plants use nutes, and water.... if they use more water than nutes ur ppm stays up, but if ur seeing large ppm swings when u check, you'll wanna top off w/ nute water, often mid-late flower u topoff w/ nutes rather than water
 
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