Autos v. Photos - A 5x5 No Rules Fight for Yield: A Jon & NickHardy Gig

[Jon]

for a 5 x 5 x 9 you should hang 1200 watt s divided by 25 = 50 watts per sq ft.. just adjust height of light for the plants.. no co2.

50 watts per sq ft?!!! I always thought it was 35-40 without CO2. You mean so I could add CO2 later and already be covered? If I wouldn’t get to 100% with a 900 how would I with a 1200?

Got the quotes: less expensive than I thought by a couple hundred!

 

[Wastei]

50 watts per sq ft?!!! I always thought it was 35-40 without CO2. You mean so I could add CO2 later and already be covered? If I wouldn’t get to 100% with a 900 how would I with a 1200?

Got the quotes: less expensive than I thought by a couple hundred!

More is not necessarily better when it comes to light intensity, especially if you're growing in a tent with low ceiling. I have a hard time using a 650w Led to its full potential in a 4x4 with 8 foot ceiling. Without CO2.

If you're able to dial down with a dimmer and run the fixture closer to the canopy you might even yield better result than running at full power at higher distance to the canopy because the plant can use more of the light. It's a balancing game between light intensity, height from canopy and coverage and what actually optimal at different growth stages.

As an example someone could run a 650w LED fixture at say 400w and still yield more than someone running the same fixture at full power, it's all about how its being used and what light is actually usable for the plant without causing negative stress.

Cheers!

 

[NickHardy]

I’m at max 1000w now, less maybe 20% left on the UV. Not had Co2 today. Luckily i raised the lights to pretty much the max I can yesterday. I can get another 2.5” maybe but think they’ve stopped stretch. They had 10 days post flip before I started counting flower and Day #10 Flower ending in a couple of hours.

1350 at edges yesterday. About half touching/through the bars. Now they have 4” minimum. Some plenty more - 12”+

 

[Absorber]

Im looking forward to seeing this play out ,the head room is going to be riveting entertainment

I’m at max 1000w now, less maybe 20% left on the UV. Not had Co2 today. Luckily i raised the lights to pretty much the max I can yesterday. I can get another 2.5” maybe but think they’ve stopped stretch. They had 10 days post flip before I started counting flower and Day #10 Flower ending in a couple of hours.

1350 at edges yesterday. About half touching/through the bars. Now they have 4” minimum. Some plenty more - 12”+

 

[Porky82]

Morning @NickHardy - hope you dig this….

While you’re playing checkers, I’ll be playing chess. The second picture is our board.

Heh.

Gold!!

 

[NickHardy]

Lets call mine 150cm in that tent. Its too tall anyway. I flipped too late waiting for something else.

But I’m using that current 5x5 grow with the 1000w first time use dial it in. Along with the 4x4 and 16oz solos with only 480w.

I read someone, a commercial grower writing on a sensor manufacturers website talking about the most he would want would be:

1300 PPM
1300 PPM Co2
1300 PPFD
1.6kwa VPD

With my nutes EC 2.4 probably around 1300 PPM comparable so that’s what I’m kinda targetting - well handily its sorta been like that the last few weeks since flip!

I’m def growing the same 12 seeds though.

Got some trellis thoughts too.

 

[Jon]

More is not necessarily better when it comes to light intensity, especially if you're growing in a tent with low ceiling. I have a hard time using a 650w Led to its full potential in a 4x4 with 8 foot ceiling. Without CO2.

If you're able to dial down with a dimmer and run the fixture closer to the canopy you might even yield better result than running at full power at higher distance to the canopy because the plant can use more of the light. It's a balancing game between light intensity, height from canopy and coverage and what actually optimal at different growth stages.

As an example someone could run a 650w LED fixture at say 400w and still yield more than someone running the same fixture at full power, it's all about how its being used and what light is actually usable for the plant without causing negative stress.

Cheers!

Thanks @Wastei - yes, agreed on all counts, of course. However - there is an element of truth to more light = bigger and denser buds…to a point. What you’re calling the balancing act I think of as always trying to get right up to the edge and maybe even peer over a little. Lol. I know light pretty well. I’m currently in search of the answer to the question raised a couple posts back - what is the sweet spot in terms of watts/sq. ft.? There’s a number I believe, strain specific obviously, but there’s a number for each. If you research it you get answers all over the board, but most seem to think upper 30s to 40 sans CO2. I do have CO2 in my future, and that’s another consideration here - at that point, I DO want the wattage and can get to high outputs. And my tent, 2 of the 3 5x5s, are 9’ tall. So I’m thinking that for say, the future CO2 tent (I’ll start with one to learn it cold first), it might make sense to go big now, dial it down as you say when using it pre-CO2, and have the ability to crank it later on. Anyway, random light thoughts.

 

[Jon]

I’m at max 1000w now, less maybe 20% left on the UV. Not had Co2 today. Luckily i raised the lights to pretty much the max I can yesterday. I can get another 2.5” maybe but think they’ve stopped stretch. They had 10 days post flip before I started counting flower and Day #10 Flower ending in a couple of hours.

1350 at edges yesterday. About half touching/through the bars. Now they have 4” minimum. Some plenty more - 12”+

Yep. I go 1350 at times. The Blackberry Moonrocks tops are about there.

 

[InTheShed]

If you're able to dial down with a dimmer and run the fixture closer to the canopy you might even yield better result than running at full power at higher distance to the canopy because the plant can use more of the light.

I was under the impression that you got better light penetration with the fixture further away at higher wattage than closer at lower wattage (given identical PPFD readings at the canopy).

And my tent, 2 of the 3 5x5s, are 9’ tall.

Your tent is 9' but your reservoir plants start at least 2-3 feet off the floor, eliminating any height advantage, no?

 

[DeltaDubie]

I’m at max 1000w now, less maybe 20% left on the UV. Not had Co2 today. Luckily i raised the lights to pretty much the max I can yesterday. I can get another 2.5” maybe but think they’ve stopped stretch. They had 10 days post flip before I started counting flower and Day #10 Flower ending in a couple of hours.

1350 at edges yesterday. About half touching/through the bars. Now they have 4” minimum. Some plenty more - 12”+

wow think your out of room those cola grow another 6 inch to a foot or more... think u vegged too long..

 

[DeltaDubie]

50 watts per sq ft?!!! I always thought it was 35-40 without CO2. You mean so I could add CO2 later and already be covered? If I wouldn’t get to 100% with a 900 how would I with a 1200?

Got the quotes: less expensive than I thought by a couple hundred!

you can do better grow with a few 100 more watts get the next light sizes up.. 900 is short on power around
the out side of the 5 x 5... 50 per sq ft is about the max unless you add co2 boost

you can grow a small bush in the centre of the tent ..

1260 watts in this pic..

20231226_191339.jpg

• DeltaDubie
• Dec 26, 2023

 

[Wastei]

I was under the impression that you got better light penetration with the fixture further away at higher wattage than closer at lower wattage (given identical PPFD readings at the canopy).

Your tent is 9' but your reservoir plants start at least 2-3 feet off the floor, eliminating any height advantage, no?

Like I wrote in my earlier post it's a balancing game between light intensity, coverage and distance to the canopy? It all depends on what's under said light?

There's many variables like plant count, veg time and final plant height at harvest that should all be taken in to consideration when dialing in optimal light intensity from plant response.

The only way to take full advantage of a high output LED fixture is with bigger and better coverage IMO. it's almost impossible to run them optimally in commercial grow tents with limited ceiling and coverage. A less stressed plant yield way more than a plant that's been light stressed throughout its life cycle.

 

[Wastei]

you can do better grow with a few 100 more watts get the next light sizes up.. 900 is short on power around
the out side of the 5 x 5... 50 per sq ft is about the max unless you add co2 boost

you can grow a small bush in the centre of the tent ..

1260 watts in this pic..

20231226_191339.jpg

• DeltaDubie
• Dec 26, 2023

Got any numbers to support your claims? With that amount of light you should aim to yield 1.5kg ~3 pounds at harvest? No?

Like have you logged one run with ~650w compared to what you're currently using 1260w? How would you otherwise know the difference? Your plants look stressed and light bleached to be fully honest.

All the best of luck!

 

[NickHardy]

you can do better grow with a few 100 more watts get the next light sizes up.. 900 is short on power around

(My writing crossed @Wastei

Yep spent quite a lot of time talking about how and why I vegged too long in my current 5x5 journal!

But on the vertical now not expecting more growth.

They’re 21 days from flip. Transition/Stretch is done and I’m comfortable running 2” from the lights.

I think watt/sqf is way too basic a number.

My 13 plants sit in a 90x110cm metal pallet I had cut to support the pots. Above them is 105x105 light, i can walk inside around my tent almost. I have 2/12 plants outside of my light direct foot print and then just a few colas. 5x5 doesnmt really play the way you calculate it.

Also 50w of what sort of light? At what stage of growth? You need to factor in the K of light at each stage, veg and flower to be basic about. Of nore interest is the PPFD as that accounts for what the 50w is delivering - the Photon phone app popular for PPFD, DPI and Lux you need to use different colour models depending on T5, CFR, HPS, CMH, LED Full, LED w/t red LED w/t infra etc.

My light neter gives me a full spectrum reading (not the UV bit though)

Because I have 3 dimmers UV - 3000k - 5000k I can manipulate that curve depending on where I’m at in the grow, granted its for large scale commercial and I’m not that, learning though.

But a rule of thumb of x watts per sq/ft dunno its of any use. Because you start doing it with HPS/CMH that changes your whole grow way more with your environment change and all that heat so maybe you want different level of light because you got some humidity issues.

But yeah tent size and watts per nope never gonna convince me its of value - especially fixed numbers with no range.

As an example my watts per are

Based this on my tray size

Converted it to feet and rhen divided 1000 by 10.65 and got 94w per sq/ft

Dunno its helpful to me?

Its far more nuanced I think, shapes of the plants even, grow style and for sure growth stage ldo

Nick

 

[InTheShed]

The only way to take full advantage of a high output LED fixture is bigger and better coverage IMO.

Right, and better coverage (and penetration) would be to run them further off the tops at the same PPFD rather than closer in at lower wattage. Again, I believe this to be untrue:

If you're able to dial down with a dimmer and run the fixture closer to the canopy you might even yield better result than running at full power at higher distance to the canopy

...even with the qualifier "might" in there. As @Graytail has always said:

More headroom gets you wider dispersion AND a deeper canopy.

 

[NickHardy]

Right, and better coverage (and penetration) would be to run them further off the tops at the same PPFD rather than closer in at lower wattage. Again, I believe this to be untrue:

...even with the qualifier "might" in there. As @Graytail has always said:

Sorry some double negatives in there and ai’m unsure of something.

@Mars Hydro for all their LEDs have an interesting sizing on all their lights.

The FC6500 they rate as 5x5 for Consumer or Enthusiast or whatever and 4x4 for Commercial. They also give hang heights (8”) for Co2 which was great for us starting out. 4” is fine

But that’s your coverage thing. The top height they give without Co2 is your 730w will fill a 5x5 at 16” but in a 4x4 do it at 12”

Height versus space - I’m growing in basically a smaller space with the lights so low but that’s OK - I keep 90% the plants directly under the light - I don’t need to diffuse the light over a wider area.

 

[InTheShed]

I didn't see a double negative but:

I don’t need to diffuse the light over a wider area.

Even if your LED diodes cover the canopy edge to edge you will still get better light penetration at higher wattage with more distance.

 

[NickHardy]

I didn't see a double negative but:

Even if your LED diodes cover the canopy edge to edge you will still get better light penetration at higher wattage with more distance.

Mine are 100% maxed 1000w with full canopy coverage (95% nothing a tidy up can’t fix) at like average 8”. Of ai could raise them how do I gain? Reflections off the walls? My pool playing mind can see those angles of refraction and reflection but then I’d be putting tin foil on my drainage trays / I’m def actually doing that anyway!

But yeah the higher bit I see HPS hung at 2-3 metres in big grows LEDs always closer and denser. The capital cost of an HPS is so much cheaper at bulk rates - $150 v, $500 that with the double whammy you need more per sq/ft is why so many commercial grows still use them. Start up costs lower, we’ll opex the electricity and when they’re 3m up in a warehouse cooling costs not such a big thing.

 

[InTheShed]

Of ai could raise them how do I gain?

If you're maxed out then your situation isn't applicable here. I was responding to the idea that one might be better off running at lower wattage closer in than higher wattage from a greater distance. That could work with a very shallow canopy (though there's no reason for it to increase your harvest, just lower your electric bill), but if you need light below that, higher wattage from further away increases penetration.

 

[NickHardy]

If you're maxed out then your situation isn't applicable here. I was responding to the idea that one might be better off running at lower wattage closer in than higher wattage from a greater distance. That could work with a very shallow canopy (though there's no reason for it to increase your harvest, just lower your electric bill), but if you need light below that, higher wattage from further away increases penetration.

Yeah I think what I said was applicable only because we’re all trying to say there’s many ways to fry an egg (or a plant!)

My only real contention is watts in space has little relevance.

If nothing else it made me realise thst my drip trays in current 5x5 are black. Covering them with something very reflective with holes in to still allow drainage yet giving bonus lights to the lower levels. Even some reflective boards like photographers use on the sides, might be like cheap side lights…

Eyes on the prize! Jon will have some tricks up his sleeve!