Indoor Best LED spectrum for vegging Autos?

[growgreenjr]

New to the forum here, first post.

I'm planning to use a 4K, 600W MH bulb in my indoor tent over 5 Fastbuds Gorilla Glue autos in Happy Frog, 5 gal fabric pots (my first autos). I'll use a 18/6 light schedule and keep the 4K bulb in there 'til the end; I may switch in a 10K 'finisher' bulb for the last week or so (that's an MH bulb as well, ultra-high UV). My feeling is that the 4K bulb is a start-to-finish, one-bulb-does-all solution (I'm used to swapping in different bulbs to initiate the photo process). I'd like to hear from experienced auto-growing experts on their opinions on this lighting choice; I also have HPS bulbs in 600W &1000W available to use.

The 4K bulb in 600W is huge; heavy and well-made. Hope it lasts! TIA for any/all replies!

 

[918AutoGrower]

I think 4k or higher for veg. 6500 would be badass!

6500k QBs would not be bad ass. When I built my 2nd QB, I mixed some 3500k boards, 4200k boards, and 5000k boards. Before I did this, I contacted HLG and asked them about 6500k QBs. HLG told me that they do not deliver the results that you think they would. They did some testing with them and decided not to produce them for sale. They don’t sell 5000k either.



“Tyranny anywhere is a threat to freedom everywhere.” — someone awesome

 

[918AutoGrower]

I have not. I’ll go look for them and compare them.Theyre definitely more expensive and require a heat sink, which these new Samsung boards DO NOT. So, using them in a build would more than double the price of the light. I’m not opposed to spending more money for a better light; but for probably 2.5x more money, I’d want a pretty major performance bump and I don’t know if that’d be the case in a veg light. There are a couple of LED gurus I know on another site that can explain any differences to me. I can assemble them just fine but as for comparing their specs and configuring then with the perfect driver to create an efficient system that produces the best bang for your buck.....I trust their judgement. They’re all photo growers, mainly, though. So, I wanted to check in with the Auto experts here at AFN. Thanks Dudeski!

Who told you that the new Samsung diodes / boards don’t need heatsinks? They absolutely need heatsinks. On HLG’s website you’ll see this statement over and over:

“May require an Aluminum plate or heatsink if running 75+ watts. Heatsink requirements depends on application and power.”

Some of the quantum boards do not need heatsinks but it isn’t because of the new Samsung diodes. The HLG-65, HLG-100, HLG-120, and HLG-132 boards do not need heatsinks because the maximum voltage, current, wattage, and μmoles/joule can be reached without those boards generating enough heat to justify the need for passive cooling by means of a heatsink. This is nothing new however since those models / versions of HLG quantum boards have never required heatsinks.

The 288-boards (both V1 and V2 diodes), the 304 boards, and the new QB-96 boards (HLG’s most recent product release), ALL need heatsinks after a certain amount of wattage. I believe it is around 75 watts. So, if you are using one of their larger boards that I just mentioned, but you use a driver that will not power the board more than 75 W, then it doesn’t need a heatsink. But if you want to push the boards to their maximum potential, you absolutely need a heatsink.

So, you can use any of the quantum boards without a heatsink if you’d prefer to drastically under power them for the entirety of the grow. Otherwise, you gotta have heatsinks. Or run an active cooling system with computer fans. But I wouldn’t recommend doing that.

Hope that helps.



“Tyranny anywhere is a threat to freedom everywhere.” — someone awesome

 

[DTOM420]

Who told you that the new Samsung diodes / boards don’t need heatsinks? They absolutely need heatsinks. On HLG’s website you’ll see this statement over and over:

“May require an Aluminum plate or heatsink if running 75+ watts. Heatsink requirements depends on application and power.”

Some of the quantum boards do not need heatsinks but it isn’t because of the new Samsung diodes. The HLG-65, HLG-100, HLG-120, and HLG-132 boards do not need heatsinks because the maximum voltage, current, wattage, and μmoles/joule can be reached without those boards generating enough heat to justify the need for passive cooling by means of a heatsink. This is nothing new however since those models / versions of HLG quantum boards have never required heatsinks.

The 288-boards (both V1 and V2 diodes), the 304 boards, and the new QB-96 boards (HLG’s most recent product release), ALL need heatsinks after a certain amount of wattage. I believe it is around 75 watts. So, if you are using one of their larger boards that I just mentioned, but you use a driver that will not power the board more than 75 W, then it doesn’t need a heatsink. But if you want to push the boards to their maximum potential, you absolutely need a heatsink.

So, you can use any of the quantum boards without a heatsink if you’d prefer to drastically under power them for the entirety of the grow. Otherwise, you gotta have heatsinks. Or run an active cooling system with computer fans. But I wouldn’t recommend doing that.

Hope that helps.



“Tyranny anywhere is a threat to freedom everywhere.” — someone awesome

Actually, HLG told me they don’t need heatsinks or ANY thermal interface or active cooling system.
I didn’t mean that these new boards, the version 2, are somehow different and suddenly now not needing heatsinks. I’m only waiting on the V2 because of the improved efficacy. These particular boards did not need heatsinks in the V1 either. Here’s a link to them on the HLG website (in the 3000k, which is not what I’m looking for) for you to check out: https://horticulturelightinggroup.com/products/qb120-quantum-board

I know a couple guys that built veg lights with the V1 and really liked them - very cheap to build and very effective. HLG recommended waiting for the V2 to drop.

 

[918AutoGrower]

I think there was a misunderstanding when you spoke to HLG. What they say on their website is “no thermal interface MATERIAL or heatsink is required.”

That exact statement is on their product description for the QB-120 and QB-132.

What they are saying is that no thermal paste or thermal sticky pad isn’t needed between the board and the heatsink...and/OR no heatsink at all is needed with a certain quantum board.... thermal paste (thermal interface material) is often used to fill in the tiny imperceptible blemishes on the back of the quantum board and also the heatsink. The thermal paste / interface material acts as a bonding agent but also provides a more uniform, flat surface that can more easily disperse heat generated by the light so that no hotspots between the board and heatsink will develop under use. The heat is evenly distributed this way by using a thermal paste or interface material.

As I stated in my first response, some of them simply do not need heat sinks because the quantum board’s maximum levels it was designed to operate under do not generate enough heat to justify needing a heat sink. This is why HLG designed some of their smaller boards with the LED diodes separated and further apart from each other… So the heat is evenly dispersed in an efficient way without the need for a heatsink. But this is NOT true for all of their boards.

HLG does not mention the thermal interface material or not needing a heatsink for several of their quantum boards because for those boards, you DO require the use of a heatsink. That’s why the sell quantum boards WITH heatsinks.

If you look at the QB-96 Elite V2, they do not make that statement. For that board, HLG states, “ heat sink and thermal pad is required to run board over 500mA or over 25 watts.” The QB-96 Elite V2 light comes with a heatsink and it comes with a thermal interface pad that is sticky on both sides. It is meant to go between the board and the heatsink. If heatsinks weren’t needed, I wonder why HLG is insisting on the use of a heat sink with their QB-324, QB-96 Elite V2, 260W QB V1 Kit, QB288 boards, QB304 boards, ... basically the rest of their products besides the QB-65, 100, 120, and 132s.

On those products, you’ll find statements in the product details that say “no thermal interface material is required between the LED board and the heatsink.” (Implying that the heatsink is required but not the thermal interface material that would go between the two)

On their QB288 board product description, it reads, “May require an aluminum plate or heatsink if running 60+ watts. Heatsink requirements depends on application and power.“ — which is almost exactly what I stated in my first response.




“Tyranny anywhere is a threat to freedom everywhere.” — someone awesome

 

[DTOM420]

I think there was a misunderstanding when you spoke to HLG. What they say on their website is “no thermal interface MATERIAL or heatsink is required.”

That exact statement is on their product description for the QB-120 and QB-132.

What they are saying is that no thermal paste or thermal sticky pad isn’t needed between the board and the heatsink...and/OR no heatsink at all is needed with a certain quantum board.... thermal paste (thermal interface material) is often used to fill in the tiny imperceptible blemishes on the back of the quantum board and also the heatsink. The thermal paste / interface material acts as a bonding agent but also provides a more uniform, flat surface that can more easily disperse heat generated by the light so that no hotspots between the board and heatsink will develop under use. The heat is evenly distributed this way by using a thermal paste or interface material.

As I stated in my first response, some of them simply do not need heat sinks because the quantum board’s maximum levels it was designed to operate under do not generate enough heat to justify needing a heat sink. This is why HLG designed some of their smaller boards with the LED diodes separated and further apart from each other… So the heat is evenly dispersed in an efficient way without the need for a heatsink. But this is NOT true for all of their boards.

HLG does not mention the thermal interface material or not needing a heatsink for several of their quantum boards because for those boards, you DO require the use of a heatsink. That’s why the sell quantum boards WITH heatsinks.

If you look at the QB-96 Elite V2, they do not make that statement. For that board, HLG states, “ heat sink and thermal pad is required to run board over 500mA or over 25 watts.” The QB-96 Elite V2 light comes with a heatsink and it comes with a thermal interface pad that is sticky on both sides. It is meant to go between the board and the heatsink. If heatsinks weren’t needed, I wonder why HLG is insisting on the use of a heat sink with their QB-324, QB-96 Elite V2, 260W QB V1 Kit, QB288 boards, QB304 boards, ... basically the rest of their products besides the QB-65, 100, 120, and 132s.

On those products, you’ll find statements in the product details that say “no thermal interface material is required between the LED board and the heatsink.” (Implying that the heatsink is required but not the thermal interface material that would go between the two)

On their QB288 board product description, it reads, “May require an aluminum plate or heatsink if running 60+ watts. Heatsink requirements depends on application and power.“ — which is almost exactly what I stated in my first response.




“Tyranny anywhere is a threat to freedom everywhere.” — someone awesome

Goodness gracious. I know that most of their boards need heatsinks. I’ve already built some from HLG and I never said or implied that all V2 boards didn’t need them. But the particular board I mentioned in my original post does not - the QB120. You have misread or misinterpreted what I wrote. I appreciate the attempt to help but I’m not interested in talking about heat sinks or getting into a debate about wording. I’ll follow the manufacturers instructions that have worked out quite well up until now. If you have some input on spectral differences for autos, I’m all ears.

 

[918AutoGrower]

Goodness gracious. I know that most of their boards need heatsinks. I’ve already built some from HLG and I never said or implied that all V2 boards didn’t need them. But the particular board I mentioned in my original post does not - the QB120. You have misread or misinterpreted what I wrote. I appreciate the attempt to help but I’m not interested in talking about heat sinks or getting into a debate about wording. I’ll follow the manufacturers instructions that have worked out quite well up until now. If you have some input on spectral differences for autos, I’m all ears.

Lmao yep I sure did. My bad dude! I think I was trying to do too much at once and misread your post.

As far as QB spectrum for autos, man I really love putting my autos under the new QB-96 Elite V2s. They have the far red added to those boards and I have noticed a much better result on my autos with the QB-96. My plants are getting more stretch when they start flowering compared to when they were growing under my HLG-260XW in 3000k. Since you’ll be lucky to get a full 30 days of veg from most autos, I often end up with short, fat autos. The additional red in the QB-96 ...it causes the plants to stretch more than it would under a standard QB. My autos are definitely taller and fuller under the QB-96s. Hope that helps. Sorry again.



“Tyranny anywhere is a threat to freedom everywhere.” — someone awesome

 

[DTOM420]

Lmao yep I sure did. My bad dude! I think I was trying to do too much at once and misread your post.

As far as QB spectrum for autos, man I really love putting my autos under the new QB-96 Elite V2s. They have the far red added to those boards and I have noticed a much better result on my autos with the QB-96. My plants are getting more stretch when they start flowering compared to when they were growing under my HLG-260XW in 3000k. Since you’ll be lucky to get a full 30 days of veg from most autos, I often end up with short, fat autos. The additional red in the QB-96 ...it causes the plants to stretch more than it would under a standard QB. My autos are definitely taller and fuller under the QB-96s. Hope that helps. Sorry again.



“Tyranny anywhere is a threat to freedom everywhere.” — someone awesome

Man, no worries!

This is exactly the kind of info I was looking for, actually. Since I have a 5x5 tent that’s currently got a couple photos flowering 4-6 weeks left) along with some autos finishing up, in that tent I have an HLG 600H kit with 4 V2 boards (I forget the designation number but they still have the kit) and it’s 3000k. My idea was to build a dedicated veg tent. I figured I could build an inexpensive light and put it in a cheap tent just for vegging and then move them a couple feet to a flower tent. It’d be hard to spend enough to double my current setup, as nice as it is; but I wanted to increase my vegetative growth rate. I kinda felt like I didn’t get very rapid growth in veg from that big 3000k light. But heck, it could be due to all sorts of things besides that light, from my soil choices to nutes to bag luck. Lol!

Do you know what the spectrum is on this QB96 Elite V2 boards is? I mean, is it 3000k, 3500k, 4000k, etc? Also, do you know how many I’d need for a great veg light in a 4x4? Don’t the 3000k lights have more red than the 4000k that have more blue? I thought that blue was better for veg and red better for veg, generally speaking?

There are some DIY light gurus on a couple other forums I visit occasionally that are really good on all the tech specs and finding the best bang for your buck for your particular need. If you’re not sure, I can ask over there. Neither those boards OR the ones I originally posted about (recommended by those gurus) are currently available, so I’m still waiting either way.

 

[DTOM420]

@918AutoGrower

Related question: since I’ve got that 600w HLG light running full bore in the flower tent, would I be almost as good just putting my Auto seedlings in there almost from the get-go? Or, would a less (1/3) powerful light in 4000k that’s running 20/4 be better? I have no idea how that trade off works. More light for less time or less light for more time on autos?

 

[918AutoGrower]

Man, no worries!

This is exactly the kind of info I was looking for, actually. Since I have a 5x5 tent that’s currently got a couple photos flowering 4-6 weeks left) along with some autos finishing up, in that tent I have an HLG 600H kit with 4 V2 boards (I forget the designation number but they still have the kit) and it’s 3000k. My idea was to build a dedicated veg tent. I figured I could build an inexpensive light and put it in a cheap tent just for vegging and then move them a couple feet to a flower tent. It’d be hard to spend enough to double my current setup, as nice as it is; but I wanted to increase my vegetative growth rate. I kinda felt like I didn’t get very rapid growth in veg from that big 3000k light. But heck, it could be due to all sorts of things besides that light, from my soil choices to nutes to bag luck. Lol!

Do you know what the spectrum is on this QB96 Elite V2 boards is? I mean, is it 3000k, 3500k, 4000k, etc? Also, do you know how many I’d need for a great veg light in a 4x4? Don’t the 3000k lights have more red than the 4000k that have more blue? I thought that blue was better for veg and red better for veg, generally speaking?

There are some DIY light gurus on a couple other forums I visit occasionally that are really good on all the tech specs and finding the best bang for your buck for your particular need. If you’re not sure, I can ask over there. Neither those boards OR the ones I originally posted about (recommended by those gurus) are currently available, so I’m still waiting either way.

The QB-96 Elite V2 are a little different than the other quantum boards in that they are not offered or classified in different color temps / spectrums like the rest of the quantum boards. I suspect this is largely due to the addition the 630-660nm far red diodes on the board. Regarding colors in the spectrum, HLG simply says that the QB 96 elite V2 has a higher CRI rating than the other lights, meaning that it contains a wider spectrum than any of the other lights they have manufactured to date. If you have read up on your CRI and what that means and it’s significance regarding indoor grow lights, this is kind of a big deal.

In a 4 x 4 tent, you would need 4 QB-96 rigs. I know this because the same week they came out, I engaged in a Facebook cha my with HLG and asked them a bu ch of questions about this new QB-96 Elite V2 that, from what I saw and read, appeared to be not much larger than a business card! The person I spoke to from HLG said that “4x QB-96 lights would absolutely dominate a 4 x 4.....for veg and for flowering.” Those are HLG’s words.

You are correct to assume that 3000k lights are more geared towards flowering and 4000k lights are engineered closer to a veg light. HOWEVER, the whole “blue for veg and red for flower” came out of the blurple era (which is dying out thanks God) where all we had for LED grow lights was blue + red = blurple! But to answer your question, you could grow a plant in veg with a blue light, but the plant won’t develop to its full potential and will likely be very leggy / too stretchy because plants — especially cannabis — need FULL spectrum light to flourish in veg and in flower. In the same manner, you don’t want to flower with JUST a red light. Plants benefit from the yellows and greens under a full spectrum light source and you want to expose your plants to as much true full-spectrum light in veg and in flour as you can. If you’ll notice, when newer growers ask if they should use both the veg and the bloom switch on the LED light when they are in veg, most experienced growers will tell them to use both because the plant will develop closer to its full potential if it has full spectrum light.

I have never been more sure, but if it would give you warm fuzzies, ask other experienced growers who have used or are using the QB-96. It is one bad-ass light, my friend. For the price, you absolutely will not find a better light.



“Tyranny anywhere is a threat to freedom everywhere.” — someone awesome