Fine-tuning my 6x6, looking for advice

I’ve recently scaled up my grow, and I’m looking for advice to fine-tune it. Wondering if anyone was interested to take a look and offer their opinions?

You’ll find some photos below. Its a 6x6 tent - slightly larger than I wanted, but the price was too good to refuse. At the moment I’m flowering 2 plants (Hindu Kush and Critical+2.0), but for the next run I’ll flower 4 at a time, to make use of the 6x6 space. I’m using 10gal & 15gal smart pots with no-till organic soil. Third run on this no-till style, and after making many mistakes I think I'm finally getting somewhere! The Hindu Kush is the largest and healthiest plant I've grown to date, which is reassuring that the no-till journey was worthwhile.

For the 2 plants in early flower, I’m running 2x HLG 288 V2’s, with the dimmer maxed out (200w at the wall per light, so 400w total). Light distance, I’m going with 15” from canopy, which seems to balance the spread and intensity fairly well (does that sound OK?)

I also own 2x COBkits light engines that max out at 160w from the wall. These are currently being used in my veg area, dimmed down to around 40w. But when I start flowering 4x plants at once, the COB’s will be moved into the flowering tent and I'll use another light for veg.

My main questions are about lighting. For the 2 plants currently in early flower, is 400w of lighting enough? If you check the photos you’ll see the larger plant (Hindu Kush) has some outer leaves receiving noticeably less light. This plant is around 4 foot wide. I’m thinking I might need to move the COB’s into the flower tent now... but where should should they be positioned? Maybe on a 45 degree angles on either side of the plants, to create some side lighting? So the configuration of the 4 lights would be a diamond, with the two outer COB's aimed towards the middle of the diamond.



In the longer term, do I have sufficient lighting for a 6x6? The total amount is 720w, via 2x HLG 288’s and 2x COBkits light engines. 

I have read that traditionally, minimum 1000w is recommended for a 6x6… But have also read that modern LED’s like the Quantum Boards and COB’s that I’m using, are far more effective than traditional grow lights, and you can get away with less wattage. So I’m a bit unsure what to do.

 If I was to purchase more lights for my flower tent, what should I be looking at, eg. supplemental/side lighting or more 'main' lights?

Thanks for reading, I look forward to hear anyones thoughts, comments, tweaks etc on my setup. Thanks in advance!

By the way, the black things on top of the lights are USB-powered computer fans (AC Infinity). When the lights are set to maximum, I found the heat-sinks too hot to touch. Figured that's not ideal for LED's lifespan, and I'd rather have that heat dispersed in the tent (I live in a cooler part of the world, my temps are on the low side). With the computer fans sitting on top, the heat-sinks are a comfortable warm temperature, and the fans distribute warm air around the tent.

720 watts for a 6x6 might be on the low side. I have 560 watts in my 2' x 4'. Even with the newer LED's, 50 watt/sq. foot (1800 total watts) would get you a good crop.

But 70 watt/sq. foot (2700 watts) would get you a REALLY good crop.

... correction - 2520 watts.

I dont think the wattage here is the issue as much as the spread is.
Id pick up 2 more boards and put 2 boards over each plant.

In your first picture, its really easy to see where all your light is concentrated. Aim to light up some of the shady parts of the plant.

Beautiful plants man! Nice sized bushes are always fun to grow.

Personally I still run hps, and I use 1000 w in an air cooled xl reflector to cover a 4x4 flood tray. The bulb is typically about 14 inches from the canopy to balance penetration and coverage.

I will be switching to LED eventually. I just can't afford the upgrade at this point. When I do I will still be running 1k worth of LED. Personally I think the idea of "getting by with less" is boring.

The difference will be that the LED will have a better spectrum, and a way better spread and coverage. So the 1k will be spread nicely over the 5x5 canopy rather then the single central bulb.

So what's my point.....

I say maximiZe your lighting if you can afford to. In a 6x6 space I'm inclined to think 4-6 LED panels over the tops and 4 cobs on the sides one in each corner. Then if you wanna get real serious put a 400 or 600w hps or a 315cmh in the middle in a cool tube hanging vertically.

Thundercat said:

Beautiful plants man! Nice sized bushes are always fun to grow.

Personally I still run hps, and I use 1000 w in an air cooled xl reflector to cover a 4x4 flood tray. The bulb is typically about 14 inches from the canopy to balance penetration and coverage.

I will be switching to LED eventually. I just can't afford the upgrade at this point. When I do I will still be running 1k worth of LED. Personally I think the idea of "getting by with less" is boring.

The difference will be that the LED will have a better spectrum, and a way better spread and coverage. So the 1k will be spread nicely over the 5x5 canopy rather then the single central bulb.

So what's my point.....

I say maximiZe your lighting if you can afford to. In a 6x6 space I'm inclined to think 4-6 LED panels over the tops and 4 cobs on the sides one in each corner. Then if you wanna get real serious put a 4-600w hps or a 315cmh in the middle in a cool tube hanging vertically.

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I also should have added that the light does need to be distributed evenly throughout the grow space and not concentrated in the middle. My bad ...

Scraping by with your lighting will be fruitless and disappointing. Tried that during my first first grow and I was disappointed that I had no fruit. These plants like lots of light.

Full spectrum LED's are great for both the veg and flower phases. All you have to do is raise the lights when required. 4 600W LED's spread evenly over the 6 x 6' with each LED having good flowering coverage of 3' x 3' should be sufficient. If you did add some COB's on the side - your plants should have bud sites up the wazoo during veg.

A 600 W HPS hung in the middle during flowering - those nuggets will be REALLY chubby.

Thanks everyone for the responses, you guys rock.

The consensus definitely seems to be MORE LIGHT! So I've moved my COB's into the tent, aimed at the sides of the plants receiving less light. 720w should be plenty for the two plants in flower.

Longer term (like next run, or whenever I use the full 6x6) - I'll aim for 1800w, but can't really spend that money right now (I only just got the tent and QB288's, which were a huge upgrade for me). Keep in mind I've only been growing a few years, it wasn't that long ago I was fooling around with 60w spacebuckets Something tells me I shouldn't rush into a setup that may be too overpowered for my 'beginner/intermediate' skill levels to make use of.

I'll have to think about which lights to choose for the 6x6. More QB288's would keep things unified, and also mean the spare parts are interchangeable, so I'm tempted to go in that direction. Also means I could scale up gradually, eg. buying another 2 boards now, and then another 2 for the next run, and so on. The only downside to this idea, I'll end up with a huge amount of drivers/cables/hangers in the tent. To avoid the mess, its tempting to look at bigger lights like the HLG550. But they seem vastly more expensive in terms of price/wattage ratio?? The HLG550 is $1000 for 500w, whereas the 288's are <$200 for 200w.

To achieve 2000w I'd need 4x HLG550's, which would cost $4400. With QB288's I'd need 10 boards to achieve 2000w, costing around $2000. Am I missing something, or are the QB288's half the price-per-watt of the 550?

I'm just thinking out aloud now. If anyone is still reading, thanks for looking over my setup and putting me in the right direction!

Disregard the suggestion of 50 watts per square ft. And 70? Wtf? And disregard the full spectrum nonsense. You have great and efficient lights now. Aim for 30 - 40 watts per square ft of quantum boards, strips, or cobs. 1800 watts over 36 square ft is ridiculous. You are 2/3 of the way there with your lights now! Starecase doesn't know what he is talking about. Put him on ignore.

Well I have to say, I'm glad to hear a different opinion, thanks for that. I've heard similar advice elsewhere - essentially that quantum boards are a different beast to all previous lights, and the old rules don't apply. The other side says that just an exaggerated marketing claim.

Now you can see my conundrum, there are vastly different opinions floating around. For a learning grower, its hard to know who is correct, or whether the answer is somewhere in the middle.

I'm going to scale things up gradually due to budget reasons. So I guess I'll stop adding lights when I find the yield/quality is high enough for my standards.

Have ordered another 2x QB288's to start. Will see how that goes for the next run, and then decide if I want to go bigger. The new lights will arrive in time to finish flowering the 2 plants I've got going, so fingers crossed I'll get a lovely result from them!

Nice setup. Mine is really close to the same, even the cold climate...lol. I wouldn’t get more lights for two reasons. It’s easier to control climate when your growing space isn’t the whole room/ tent. And secondly It’s really nice to have the extra space to just sit down, chill and check everything out. I have a bucket that holds all my malted barley for a seat in my flower room. That’s where I check my temps, humidity, plants, soil and biology. I have two 260w XL V2’s dimmed down to 200w for both my rooms. I just got them around two months ago. I started my plants out at about 30 inches away and have just let the plats grow into them. I don’t think I’ll be pushing them any closer to 18 inches when the are turned up though. They are strong lights

You guys are so funny acting like LEDs are some how some amazing revolution in lighting that makes wattage irrelevant and the inverse square law untrue. They don't. The farther away the lights are the less energy the plant is getting. I was just talking to several led growers on a thread the other day that all keep their lights at about 10-12 inches to maximize penetration but still get some spread.

The idea of dimming down your lights seems totally crAzy to me. The light is literally the food for your plant. Why try to starve it?

If I want my plant to be the best it can be I want to ensure it's got plenty of light to get that job done!

Your yield and flower quality/density are directly related to how much light you can get penetrated into your plants. So intensity plays a big roll and so does coverage. If your plants are partially in the dark they aren't reaching full potential.

I've been watching led grows for over 10 years waiting for the point that the tech reaches it's potential. Guess what it's not done yet. The lights are still getting better and they are all WAAAY over priced still for the good ones.

The good ones don't claim that 200w is as good as 500. They just produce enough light and have enough coverage to do their jobs efficiently.

Don't take any of this wrong, I like LEDs. I don't like companies making claims about power that aren't true. I get tired of new growers using LEDs and then wanting to know why their buds are small or airy. I just want to see the real tech to reach fruition and become affordable.

Big Green Thumb said:

Disregard the suggestion of 50 watts per square ft. And 70? Wtf? And disregard the full spectrum nonsense. You have great and efficient lights now. Aim for 30 - 40 watts per square ft of quantum boards, strips, or cobs. 1800 watts over 36 square ft is ridiculous. You are 2/3 of the way there with your lights now! Starecase doesn't know what he is talking about. Put him on ignore.

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i was going to say about 14-1500 watts in cobs and QBS should do you well in a 6x6.
the 50 watts per sq ft is for h.i.d. lighting. it's a good rule for hps, but overkill for l.e.d.s

Big Green Thumb said:

Disregard the suggestion of 50 watts per square ft. And 70? Wtf? And disregard the full spectrum nonsense. You have great and efficient lights now. Aim for 30 - 40 watts per square ft of quantum boards, strips, or cobs. 1800 watts over 36 square ft is ridiculous. You are 2/3 of the way there with your lights now! Starecase doesn't know what he is talking about. Put him on ignore.

Click to expand...

Be nice everyone ... 70 w / sq.ft might not be as ridiculous as one might think.

I did go with the 70 w / sq.ft in this grow using Full Spectrum LED's. I just chopped yesterday and will have my finished weight in about 5 weeks. The early returns are showing pretty dense, sticky and stinky nuggets. But I know that the final quality won't be known until curing has finished. So ...

... if my finished product isn't good, I will happily admit that I was mistaken.

StareCase said:

Be nice everyone ... 70 w / sq.ft might not be as ridiculous as one might think.

I did go with the 70 w / sq.ft in this grow using Full Spectrum LED's. I just chopped yesterday and will have my finished weight in about 5 weeks. The early returns are showing pretty dense, sticky and stinky nuggets. But I know that the final quality won't be known until curing has finished. So ...

... if my finished product isn't good, I will happily admit that I was mistaken.

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it's not that it's ridiculous, just wasting power. plants do have a threshold for how much light they can absorb in a given time. if you notice your plants starting to droop towards the end of your lights on cycle...that's because they're saturated...and now it's like you're just bouncing m&ms off of a comatose diabetics head......
some strains can take it, and love it, some will just do what they do, and ignore it once they get saturated. the trick is to pick those light hogs, if that's the way you want to go with it

I had this image of Clint Eastwood playing Roger the Shrubber. "You want some bushes and a nice path, punk?!"

Good comparison with the M & M's. I went with 35 w / sq. ft my last grow and the final results - LARF! So I doubled the wattage mainly to get full 2 x 4 coverage. I was fortunate then to find two strains that love lots of light. - 1 Red Diesel and 1 OG Kush. Pretty sure they have rewarded me.

Thundercat said:

You guys are so funny acting like LEDs are some how some amazing revolution in lighting that makes wattage irrelevant and the inverse square law untrue. They don't. The farther away the lights are the less energy the plant is getting. I was just talking to several led growers on a thread the other day that all keep their lights at about 10-12 inches to maximize penetration but still get some spread.

The idea of dimming down your lights seems totally crAzy to me. The light is literally the food for your plant. Why try to starve it?

If I want my plant to be the best it can be I want to ensure it's got plenty of light to get that job done!

Your yield and flower quality/density are directly related to how much light you can get penetrated into your plants. So intensity plays a big roll and so does coverage. If your plants are partially in the dark they aren't reaching full potential.

I've been watching led grows for over 10 years waiting for the point that the tech reaches it's potential. Guess what it's not done yet. The lights are still getting better and they are all WAAAY over priced still for the good ones.

The good ones don't claim that 200w is as good as 500. They just produce enough light and have enough coverage to do their jobs efficiently.

Don't take any of this wrong, I like LEDs. I don't like companies making claims about power that aren't true. I get tired of new growers using LEDs and then wanting to know why their buds are small or airy. I just want to see the real tech to reach fruition and become affordable.

Click to expand...

I dimmed my lights cause the plants/room don’t need an equivalent to a 1000w light until flower if you ask me. Especially little 4inch clones...lol! Why on earth would I waste power like that? But that’s my opinion and choice. The HLG’s are too strong to keep at a distance of 10-12 inches. The plants are guaranteed to have light stress if they were that close and running full power or probably even 400w. Light distance will vary depending on what LED light you are using. If I was using a fluence spider, then yes 10-12 inches would probably be ideal but not with the QB’s. Here is a video with a lighting expert from the 2018 indo expo about LED’s. They have finally surpassed hid and hps in his expert opinion. I got mine cause I am sick of dealing with the heat and wanted a lower electric bill. That’s why I made the switch after growing with hps for more than 10 years.

StareCase said:

Be nice everyone ... 70 w / sq.ft might not be as ridiculous as one might think.

I did go with the 70 w / sq.ft in this grow using Full Spectrum LED's. I just chopped yesterday and will have my finished weight in about 5 weeks. The early returns are showing pretty dense, sticky and stinky nuggets. But I know that the final quality won't be known until curing has finished. So ...

... if my finished product isn't good, I will happily admit that I was mistaken.

Click to expand...

What model lights are you using, and how many? Are you talking real watts at the wall, or "equivalent" watts? I.e., viparspectra 450 only pulls 192 watts from the wall. Same with Mars and most every cheap "full spectrum" blurple light on the market.

Timber only recommends 35 watts of cobs lighting per square foot on their website.
@CobKits
@RainDan

Hi there Thumb ...

I have 2 Viparspectra 600 W Reflector Series in a 2' x 4' x 60" tent (that's all I have room for at the moment) and each unit draws about 280 wall watts. Viparspectra use the Epiled and Bridgelux 5 w chip sets in them 600's. (Not sure how many are Epiled and how many are Bridgelux though) So 560 wall watts in that 8 sq. foot grow area.

I did start @ 35 w / sq.ft as I started with 1 of those reflector units. The Viparspectra web site also claimed that this light could cover a 3' x 3' flower area. (Ummm ... not quite there, marketing folks!)

The middle part was OK - not very dense and not very resin coated but it did look like bud should. Anything on the outer 1' on each side of the light was just larf. (I ended up losing that entire grow anyways due to the dreaded White Mildew!!)

With the 2nd unit, I found I had good coverage throughout the entire tent with the lights @ 20". They cover a 2' x 2' area well. I might drop the lights to 14" next grow. Maybe 12". I posted harvest pics - https://www.rollitup.org/t/its-the-most-wonderful-time.981560/

The buds were solid and sticky and 6 of the upper branches are nearly the size and diameter of a 750 ml water bottle. Viparspectra may be classed as "cheap blurples" but for the $520 it cost me to work in my current set-up, I think they did a pretty good job.

Ah yes, the old "HID vs LED" debate. How did I guess this would come up? Sorry guys, but I already decided on LED (quantum boards and COB only). I'm not considering HID lighting for my grow. My research shows that LED (in the right hands) can produce the same or higher quality/yield, for lower electricity usage.

I say "in the right hands" because it seems LED growing can be quite different to HID, in terms of ideal conditions, nutrient usage etc. For example I've been reading about LED-grown plants often having cal/mag problems. Some are saying that happens because LED-grown plants tend to be hungrier, and consume more cal/mag than the same plant would under HID. Theres other examples like that, leading me to believe we're learning the potential of LED. It also seems likely that growers moving across from HID might not have the best results with LED at first, until they work out the differences and adapt their conditions, nutrients etc.

bleak said:

Ah yes, the old "HID vs LED" debate. How did I guess this would come up? Sorry guys, but I already decided on LED (quantum boards and COB only). I'm not considering HID lighting for my grow. My research shows that LED (in the right hands) can produce the same or higher quality/yield, for lower electricity usage.

I say "in the right hands" because it seems LED growing can be quite different to HID, in terms of ideal conditions, nutrient usage etc. For example I've been reading about LED-grown plants often having cal/mag problems. Some are saying that happens because LED-grown plants tend to be hungrier, and consume more cal/mag than the same plant would under HID. Theres other examples like that, leading me to believe we're learning the potential of LED. It also seems likely that growers moving across from HID might not have the best results with LED at first, until they work out the differences and adapt their conditions, nutrients etc.

Click to expand...

Honestly I don't see anyone debating HID vs LED. I'm certainly not suggesting you switch, or that HID is better, once the prices come down I'm going to switch to LED as a matter of fact.

I'm saying light needs to be treated like light, instead of acting like LED light is something drastically different. The diodes might be more power efficient and the spectrums might be more effective, but they are still only light with a certain amount of power pushing it towards your plants.

All I've tried to say is that the farther away the lights are, the less light your plants are absorbing. The less light your plants get the less potential they have. Shaded parts of the plant aren't absorbing as much light as they are capable of which was why I suggested side lighting specifically. I saw an awesome LED grow the other day where the guy had QBs mounted around the plant in a circle. It looked very effective.

I'll also throw in that 200w lights are 200w lights, not 500w so treat them like 200w lights. A 200w light will effectively cover a 2x2 or 2x3 area depending on the shape. It doesn't matter if its HID or LED 200w at an effective distance will cover that area. Given those conditions I'm positive the LED grow will be better all around.

What I don't buy into is the idea that you can place 200w of light source twice as far away and still get the same performance. Once you are over 12 inches from the source the intensity exponentially drops. At 2 feet you literally are getting 1/4 of the light potential on your plants. Its the INVERSE SQUARE LAW and unless science has changed I'm pretty sure this still applies to all light sources.