DE killing plants at 5'

[sgrowdum]

Has more to do with light intensity then temperature.

I agree but therein lies the question, which is more supieror the DE @ 750 or the SE @ 1000

 

[PSUAGRO.]

Are you suggesting that 1000ppm is not enough for a 14" tall plant under a DE? When they were in soil I was feeding once every 3 days or so as that's all the were drinking. Now in coco I'm feeding once a day 1000ppm solution. Starting tomorrow I was going to expierment with twice a day

No experience in 100% straight coco,sorry..............all I know is that a 1000w DE in a 5x3 is a lot of light(photons) and heat to the canopy,transpiration rates from IR will be high,nutrient requirements will be high from co2 enrichment & 1750+ umol/s new DE bulb . Did you notice any "tacoing" of the upper leaves from the heat or just an upwards claw as you said? maybe dimming it to 750w isn't such a bad idea until you dial in your regiment/setup. Ask some vet DE/coco growers for their opinions


good luck

 

[Getgrowingson]

I ran de and coco for a couple years recently switched to organic soil. I never got over 1000ppm in full flower under de hps but I watered three times a light cycle. I would back it off to 750 and get them dialed in there and flip. After first week or two turn it back up to a 1000

 

[since1991]

Your blasting them with WAY too much light. 80 at canopy isnt bad at all. But your relative humidity is all over the map as well. Get your rh under control and I hate to tell you that the double ended hps in a closet is just too much.

 

[since1991]

I agree but therein lies the question, which is more supieror the DE @ 750 or the SE @ 1000

In his situation and room...a single ended 1000 watter (maybe on a light rail) is the fixture to use. Every one thinks doubles are the better lamp and its not necessarily so. They were never intended single lamp and in small confined spaces. They ars meant for giant greenhouse complexes and high bay warehouses...and rows of them

 

[VegasWinner]

Man I don't know where this 3' rule of thumb came from... at 5' the light is too much. After 36hrs under floros these things are back to life. Am I missing something here? Doing something wrong?

In a 3x5 space the most light you can push without CO2 is 750w @50wpsf.
If you want to run at 1000w you will have to use CO2. Your old hps does not have the same spectrum as the DE so your plants are getting to much chloroplast to convert so the leaves curl and turn yellow.

 

[Carolina Dream'n]

Are you suggesting that 1000ppm is not enough for a 14" tall plant under a DE? When they were in soil I was feeding once every 3 days or so as that's all the were drinking. Now in coco I'm feeding once a day 1000ppm solution. Starting tomorrow I was going to expierment with twice a day

You were not watering enough. My rockwool plants get watered 6 times a day. The water holding capacity of rockwool and coco isn't too different.

 

[sgrowdum]

Your blasting them with WAY too much light. 80 at canopy isnt bad at all. But your relative humidity is all over the map as well. Get your rh under control and I hate to tell you that the double ended hps in a closet is just too much.

A DE @ 1000w has been run in closets the same size as mine. "Too much" is an inaccurate statement. They can be made to work but obviously something in my setup is preventing it. Also look at my first post. I am currently running Co2 to the tune of around 850 PPM on average

 

[sgrowdum]

You were not watering enough. My rockwool plants get watered 6 times a day. The water holding capacity of rockwool and coco isn't too different.

I still don't see how feeding once a day in 100% coco isn't enough. The soil is moist to the touch 12hrs after a feeding. With that said I don't mind stepping up to two times a day to see what happens

 

[sgrowdum]

In a 3x5 space the most light you can push without CO2 is 750w @50wpsf.
If you want to run at 1000w you will have to use CO2. Your old hps does not have the same spectrum as the DE so your plants are getting to much chloroplast to convert so the leaves curl and turn yellow.

I have C02 and the room is maintaining around 850ppm

 

[sgrowdum]

Also Mods if his thread is better served in the sick plants section feel free to move it. On a side note I think the statements about the RH being too low is the culprite here. The light is very strong and if the plants aren't clicking on all cylinders they will struggle.

 

[since1991]

A DE @ 1000w has been run in closets the same size as mine. "Too much" is an inaccurate statement. They can be made to work but obviously something in my setup is preventing it. Also look at my first post. I am currently running Co2 to the tune of around 850 PPM on average

So what do you think it is thats giving you problems???

 

[VegasWinner]

is your feeding schedule keeping up with the energy available, including levels of nutrients?

 

[Moldy]

5X3 closet
8.5' ceilings
9k AC
C02
80* temps at canopy
45-70% RH
(5) 5 gallon smart pots 100% coco
Light is 5' away currently
Jacks 3/2/1 750-1000ppm

So I've determined that my DE lights at the 1000watt setting are just too much for my 5X3 closet. The plants starting acting up a few weeks back (yellowing at the centers and leaves curling upwards) i thought I was over feeding so I ditched the soil and jumped to coco. I gave the plants a week to recoup from the transition and the color started to come back and growth began again.

Last night I did a light fan leaf trim and flipped the lights from 750 to 1000 to test. This morning at 9am I took a look and the leaves started to curl back up...

Soooooo my question is which would be the better choice, turning the lights back to 750 or running my old 1000w light? Which would give me better results? I don't have a PAR meter sonic but sure.

I've got the same issue with burning/over cooked top leaves. At 1000W (AC-DE) my leaf edges curl up and some of the new leaves are burnt. Had the light about 3.5 feet above the canopy but still not far enough. Had to move down to 630W.

 

[sgrowdum]

So what do you think it is thats giving you problems???

RH

 

[sgrowdum]

I've got the same issue with burning/over cooked top leaves. At 1000W (AC-DE) my leaf edges curl up and some of the new leaves are burnt. Had the light about 3.5 feet above the canopy but still not far enough. Had to move down to 630W.

Care to share your Grow space and RH? Also I wonder if the 1000w would do better than the DE at 630?

 

[stnr420]

Man I don't know where this 3' rule of thumb came from... at 5' the light is too much. After 36hrs under floros these things are back to life. Am I missing something here? Doing something wrong?

1000 watts is way too much for a 3 x 5 im0....that is classic light bleaching.....i had this happen in a 5 x 5!

 

[sgrowdum]

is your feeding schedule keeping up with the energy available, including levels of nutrients?

I'm feeding 321 jacks around 900-1000ppm once a day in 100% coco. Each 3.5-4 gallon bag gets roughly 1 gallon of water a day. This translates to roughly 15 run off from what I'm guessing. I'm about to step it up to two gallons.

 

[sgrowdum]

1000 watts is way too much for a 3 x 5 im0....that is classic light bleaching.....i had this happen in a 5 x 5!

Oh how I wish you were wrong but it's looking like it. I put one of them under the 600 setting this morning so we'll see how it fares compared to the others under the T5's

 

[Moldy]

Care to share your Grow space and RH? Also I wonder if the 1000w would do better than the DE at 630?

4X4 max height is 7.5', RH is 20% all of the time.