Water cooling leds

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oh4show

Member
Hi all new here and I've been scratching my head for a while on if or not this will work to some degree...
If I was to place PC water cooling blocks and thermal paste on top of the led light heatsink would it help with ambient grow room temps by transfering some of the heat to water from the led light? And to an exchanger out side the room...I'm using 2 spider farmer sf4000 Evo 400 true watts in a 120cmL by 60cmW by 180cmh
 
curious2garden

curious2garden

Well-Known Mod
Staff member
oh4show said:
Thanks very much for your input sorry I dident realise there was a led section..I agree it is alot of light I'm yet to get a par meter so I can dim efficiently...might explain why a couple in the centre start to fix tail towards the last 4 weeks Tha ks very much for the reply
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No problem, moved you over to LED section and welcome to RIU.
 
Rocket Soul

Rocket Soul

Well-Known Member
Imo water cooling leds is for really high energy density leds like cobs. Also, if you lead the heat to outside the tent but still draw from the same air youll be drawing the heat back in again, in principle. Id look for a better extraction unit, and a bit less watts, depending on what leds youre using. Not all 400 w leds actually draw 400w, there was all sorts of equivalent watt shenanigans being sold before leds got serious.
 
coreywebster

coreywebster

Well-Known Member
oh4show said:
Thanks very much for your input sorry I dident realise there was a led section..I agree it is alot of light I'm yet to get a par meter so I can dim efficiently...might explain why a couple in the centre start to fix tail towards the last 4 weeks Tha ks very much for the reply
Click to expand...
400w is a lot of light in a 60cm x 120cm tent (2x4)

800w is mental !

Unless I've misunderstood your original post.

Anyway, welcome to RIU :bigjoint:
 
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1212ham

Well-Known Member
oh4show said:
Oh wow so run them about 50/60 percent power mabie in the mean time till I get a lux meter...are there any benefits of having over sized lights that can dim like efficiency or any thing...guess I got very carried away
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I'm thinking around 40% on the high end.
The UNI-T Bluetooth lux meter pairs seemlessly with the PPFD Meter app. A search here will show many posts about it.

I'm running a water cooled bar light. It's a frame of 1/2" square tube, a pump a little bigger than an ice cube and an old engine oil cooler as heat exchanger.

It's opperated by an inkbird humidity controller atm. It turns on when humidity is low, that causes the temperature controlled exhaust fan to run less and more humidity stays in the tent.

It's been a challage controlling things efficiently as our weather has been erratic again. It seems like that's the new normal the last few years.
 
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oh4show

Member
1212ham said:
I'm thinking around 40% on the high end.
The UNI-T Bluetooth lux meter pairs seemlessly with the PPFD Meter app.
Btw, I'm running a water cooled light.
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Great I'll try and find one and get this sorted..oh really I love the idea of water cooling...I was thinking of a couple of water blocks and a 240mm radiator and fans from a PC water cooling system...for some reason it intrigues me
 
curious2garden

curious2garden

Well-Known Mod
Staff member
oh4show said:
Oh wow so run them about 50/60 percent power mabie in the mean time till I get a lux meter...are there any benefits of having over sized lights that can dim like efficiency or any thing...guess I got very carried away
Click to expand...
Yes, it means you can buy a bigger tent without buying more light. Those would run a 5x5 and there's lots of GREAT Black Friday sales coming up.

Also you can run your lights dim and cool, more light is better then not enough.
 
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Delps8

Well-Known Member
If you have a non-removable driver, it could be a fun project though, personally, I'd rather spend a few hundred $$ and get a bar style light.

If you have a driver that is removable, why not just remove the driver and suspend it above the grow space?
 
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1212ham

Well-Known Member
oh4show said:
Great I'll try and find one and get this sorted..oh really I love the idea of water cooling...I was thinking of a couple of water blocks and a 240mm radiator and fans from a PC water cooling system...for some reason it intrigues me
Click to expand...
Yeah, I like to experiment, note the edit to my last post.

The only issue I see is the cooling would tend to be concentrated around the cooling block.

It might be time for experiments! I don't have any boards but I have strips, cobs and water blocks etc.
 
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Delps8

Well-Known Member
oh4show said:
Thanks very much for your input sorry I dident realise there was a led section..I agree it is alot of light I'm yet to get a par meter so I can dim efficiently...might explain why a couple in the centre start to fix tail towards the last 4 weeks Tha ks very much for the reply
Click to expand...
Yeh, fox tails can be caused by too much of a good thing.

I grow at high light levels because more light, up to the light saturation point, results in a larger crop.

One of the issues that I run into is that the light levels at the center of the PPFD map are a big higher than at the values off center, as it typical for grow lights. Simple fix is to tape a piece of bond paper around the center light bar.

Even at max power (330 watts) the temperature of the paper reaches <110*F so it's not a safety hazard. And it does drop the PPFD at that point by about 100µmol.

1731267295837.jpeg


Rather than spend the $$ on a PAR meter, why not go with a lux meter. For $26 Amazon (US) will send a Uni-T light meter. I've attached a PDF I wrote that will help with converting lux to µmol.

Insofar as setting light levels - growers go to all sorts of pains to get their grow set up but overlook the easiest way to get the best out of their plants — the dimmer.

Per the cited paper, every increase of 50µmol increased crop yield by about 5%. I can't think of an easier way to get an increase in yield than simply turning up the dimmer.


1731267497961.png

Light readings from a couple of days ago. The plant on the right is much smaller than the other one so I can't quite get the light levels where I want them.

More light gets more weed.

1731267665984.png
 

Attachments

Rocket Soul

Rocket Soul

Well-Known Member
Delps8 said:
Yeh, fox tails can be caused by too much of a good thing.

I grow at high light levels because more light, up to the light saturation point, results in a larger crop.

One of the issues that I run into is that the light levels at the center of the PPFD map are a big higher than at the values off center, as it typical for grow lights. Simple fix is to tape a piece of bond paper around the center light bar.

Even at max power (330 watts) the temperature of the paper reaches <110*F so it's not a safety hazard. And it does drop the PPFD at that point by about 100µmol.

View attachment 5438796


Rather than spend the $$ on a PAR meter, why not go with a lux meter. For $26 Amazon (US) will send a Uni-T light meter. I've attached a PDF I wrote that will help with converting lux to µmol.

Insofar as setting light levels - growers go to all sorts of pains to get their grow set up but overlook the easiest way to get the best out of their plants — the dimmer.

Per the cited paper, every increase of 50µmol increased crop yield by about 5%. I can't think of an easier way to get an increase in yield than simply turning up the dimmer.


View attachment 5438798

Light readings from a couple of days ago. The plant on the right is much smaller than the other one so I can't quite get the light levels where I want them.

More light gets more weed.

View attachment 5438799
Click to expand...
Around 50% increase from 600 to 1200 ppfd.
This is a clip from another study which both confirms and contrast those findings.
The 2 peak condition gets a 46% increase in yield but starts from a much higher position, and generally yields more than other spectrums.
Broad (extra far red from whites) is a close follower.
The light utilization efficiency (yield/dli) is also interesting as it as it brings perspective to Bugbees not finding any static differences in yield per spectrum; in both high and low light groups double red peak seems to yield more than both standard high efficiency and 660 centred lights. The 600ppfd condition is especially noteable; almost 20% more yield per dli in the double red peak condition (640/660) than any other spectrum.

Also to point out is that these tests detect very low variance in all groups which generally is a song of reliability. a,b,c,d indicates groups that are significantly the same; no significant difference.
Screenshot_2024-11-10-21-44-52-670_com.google.android.apps.docs.jpg
 
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Delps8

Well-Known Member
Rocket Soul said:
Around 50% increase from 600 to 1200 ppfd.
This is a clip from another study which both confirms and contrast those findings.
The 2 peak condition gets a 46% increase in yield but starts from a much higher position, and generally yields more than other spectrums.
Broad (extra far red from whites) is a close follower.
The light utilization efficiency (yield/dli) is also interesting as it as it brings perspective to Bugbees not finding any static differences in yield per spectrum; in both high and low light groups double red peak seems to yield more than both standard high efficiency and 660 centred lights. The 600ppfd condition is especially noteable; almost 20% more yield per dli in the double red peak condition (640/660) than any other spectrum.

Also to point out is that these tests detect very low variance in all groups which generally is a song of reliability. a,b,c,d indicates groups that are significantly the same; no significant difference.
View attachment 5438813
Click to expand...

I think you've brought that up before and it's great info. What is it about 640+660 that boosts yield? The current grow lights use 660 so what will it take to get 660 in the spectrum? If the boost is that signficant, it's worth it for cannabis growers but we're a tiny part of the overall demand.

Have you seen anything on the impact of 730? Bugbee calls it "a flamethrower".
 
Rocket Soul

Rocket Soul

Well-Known Member
Delps8 said:
I think you've brought that up before and it's great info. What is it about 640+660 that boosts yield? The current grow lights use 660 so what will it take to get 660 in the spectrum? If the boost is that signficant, it's worth it for cannabis growers but we're a tiny part of the overall demand.

Have you seen anything on the impact of 730? Bugbee calls it "a flamethrower".
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730- 4th white column, but it wasnt mono added, long tail whites + 660. Maybe like a 90cri white.
640/660 : each one lands in one chlorophyll action spectrum a and b. You need both to complete the whole cycle of photosynthesis chemically. And if you look at most standard growlights theres a big dip just around 630-640.
You know im not a super fan of Bugbee, flamethrower may have to do with his new apogee meter finally being able to measure it. Ive seen something about surprising yield increase with loads of far red added to high blue blurple but i lost track of that video. When i queried my mate who sent it he wasn't sure but it may somewhere in this one, think its westmoreland:


I didnt have to go thru it so not sure, and as usual whenever theres youtubes on proper studies you allways seem to be missing those vital details.
Personally the one light we added far reds seemed to have little effect. But it was never a very clean test. Personally im looking for good efficiency 680 diodes, pretty sure they will cover both the far red effect aswell as some other nice redsup effects. Its the peak absortion peak of the phytochrome: the actual live light harvesting organ of the plant; think some studies of "dead chloropyll" may get their peaks somewhat wrong.
This is 2700k 90cri + 405+646+680, something ill be running tests on but likely mixing if with another similar spectrum to get rid of that dip around 420nm:
IMG-20241108-WA0015.jpg
Im fairly sure there is more than just efficiency and intensity; but were talking about decimals and mainly on getting similar yields of higher quality; subjectively measured. As in unmistakable better smells and taste, which is a thing hard to demonstrate unless you do blind tests, which are hard to document in papers.

Edit: defo not that video. I just posted blind from a msg he sent me. But pretty sure its somewhere in westmorelands vids if you know them well.
 
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Jimski

Jimski

Well-Known Member
1212ham said:
Yeah, I like to experiment, note the edit to my last post.

The only issue I see is the cooling would tend to be concentrated around the cooling block.

It might be time for experiments! I don't have any boards but I have strips, cobs and water blocks etc.
Click to expand...
I am trying to find a post a guy had on a very elegant peltier cooler that with proper airflow dropped
oh4show said:
Great I'll try and find one and get this sorted..oh really I love the idea of water cooling...I was thinking of a couple of water blocks and a 240mm radiator and fans from a PC water cooling system...for some reason it intrigues me
Click to expand...
 
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