Mixed LED/HID growers. What temperature?

.Smoke

Well-Known Member
I'm thinking of mixing 400w of led along with a 1kw se hps and was wondering what temperature you guys have found is best for mixed lighting?

Stick to 75F for the HID, or closer to 85F for the led?
 

Rdubz

Well-Known Member
I would just recommend getting a infrared gun thermometer and see leaf temps and stick to VPD
 

Mike6326

Member
I have been growing inside in a tent for several years now. I use HID lighting with my main problem being heat generation and the ability to remove the heat from the tent. Recently I have been researching LED lighting to replace the HID. I Looked to all the major manufacturers but very few had info on radiant heat from the lights. I was convinced that I was going to invest in the Spider Farmer SF7000 for a 5x5 tent. I went to their site and found a video explaining the light distribution at certain heights above the plants. During the video the instructor goes to the top of the plate that hold the lights and mentioned out of hand " you cannot lay your hand on the back of the light as the temperature runs about 140 degrees F." How can you grow anything in a tent with that temperature flowing freely off the top of your light. Good HID light fixture have enclosures so you can remove excess heat. I have no problem touching my Sun Spectrum hood, temp rarely gets above 85 degrees on the outside. I see no advantage to mixing your lighting other than you will have more heat. I'm from the south, heat is my main problem. I'm attaching a couple of samples! Enjoy! By the way, the purple is caused by temperature range from 65 - 78 degrees in the tent during the last 3 weeks growth.
 

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Rdubz

Well-Known Member
I have been growing inside in a tent for several years now. I use HID lighting with my main problem being heat generation and the ability to remove the heat from the tent. Recently I have been researching LED lighting to replace the HID. I Looked to all the major manufacturers but very few had info on radiant heat from the lights. I was convinced that I was going to invest in the Spider Farmer SF7000 for a 5x5 tent. I went to their site and found a video explaining the light distribution at certain heights above the plants. During the video the instructor goes to the top of the plate that hold the lights and mentioned out of hand " you cannot lay your hand on the back of the light as the temperature runs about 140 degrees F." How can you grow anything in a tent with that temperature flowing freely off the top of your light. Good HID light fixture have enclosures so you can remove excess heat. I have no problem touching my Sun Spectrum hood, temp rarely gets above 85 degrees on the outside. I see no advantage to mixing your lighting other than you will have more heat. I'm from the south, heat is my main problem. I'm attaching a couple of samples! Enjoy! By the way, the purple is caused by temperature range from 65 - 78 degrees in the tent during the last 3 weeks growth.
Very nice buds :bigjoint: I have to agree with you it depends on your situation, I vent my HID lights out completely separate from the grow space so ya when u compare I don't use A/C in the winter if I used LED it would bring more heat and then more A/C :bigjoint:
 

farmingfisherman

Well-Known Member
Two 100 watt led boards and a 315 cmh in a tent made for a really warm 4x4 without much effort, to much actually once outside temps began to warm up.. How much space are you covering?
 

.Smoke

Well-Known Member
Two 100 watt led boards and a 315 cmh in a tent made for a really warm 4x4 without much effort, to much actually once outside temps began to warm up.. How much space are you covering?
It's a 4'x8'.
It would be 2- 600w hps and 2 of these...(300w not 400)

Basically, pull the middle hood out and replace with the leds...
20210318_193527.jpg
 

ComfortCreator

Well-Known Member
I have been growing inside in a tent for several years now. I use HID lighting with my main problem being heat generation and the ability to remove the heat from the tent. Recently I have been researching LED lighting to replace the HID. I Looked to all the major manufacturers but very few had info on radiant heat from the lights. I was convinced that I was going to invest in the Spider Farmer SF7000 for a 5x5 tent. I went to their site and found a video explaining the light distribution at certain heights above the plants. During the video the instructor goes to the top of the plate that hold the lights and mentioned out of hand " you cannot lay your hand on the back of the light as the temperature runs about 140 degrees F." How can you grow anything in a tent with that temperature flowing freely off the top of your light. Good HID light fixture have enclosures so you can remove excess heat. I have no problem touching my Sun Spectrum hood, temp rarely gets above 85 degrees on the outside. I see no advantage to mixing your lighting other than you will have more heat. I'm from the south, heat is my main problem. I'm attaching a couple of samples! Enjoy! By the way, the purple is caused by temperature range from 65 - 78 degrees in the tent during the last 3 weeks growth.
With LED, any driver that is used at 75% or more of its max gets hot. So 2 options --
1) driver is mounted outside tent or room
2) fans placed to blow over the driver and heatsink to take out that heat at a constant rate.
 

Rurumo

Well-Known Member
LEDs honestly aren't much cooler watt for watt, they just produce less ir and so cooler leaf temps, so the hot air rises and you just vent it out. The cooler temps come in when people are replacing a 1,000 hps with a 600 watt led...of course it's going to be cooler, derp. I love mixed lighting setups, I've seen some mixed cmh/led that produces beautiful quality buds. Drivers do get hot though, so to take full advantage of the reduced heat of LEDs you need to mount those puppies outside the tent.
 

farmingfisherman

Well-Known Member
It's a 4'x8'.
It would be 2- 600w hps and 2 of these...(300w not 400)

Basically, pull the middle hood out and replace with the leds...
View attachment 4858367
Great looking garden! Someday when the house is all buttoned up and I have time I'd love to do a grow of that size.
 

farmingfisherman

Well-Known Member
LEDs honestly aren't much cooler watt for watt, they just produce less ir and so cooler leaf temps, so the hot air rises and you just vent it out. The cooler temps come in when people are replacing a 1,000 hps with a 600 watt led...of course it's going to be cooler, derp. I love mixed lighting setups, I've seen some mixed cmh/led that produces beautiful quality buds. Drivers do get hot though, so to take full advantage of the reduced heat of LEDs you need to mount those puppies outside the tent.
Like these? Not sure of the quality since it was my first time out but I had plenty of flowers! 515 watts of light and I didn't have to run any additional heat. This go around is all LEDs and I'm having to run a heater to get the temps the plant likes which seems silly.
IMG_20200323_122653 (6).jpg

IMG_20200416_200307 (2).jpg
 
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