Light per square metre/feet for growing plants

[AlaskaRob]

As I am fairly new to growing, anyone able to give advice on my setup? I can list it all out, and have a separate thread listing it all, but I think this forum would actually be better for feed back. I'm going to flip the lights to 12/12 this weekend, but not completely sure what nutrients to add or subtract from my current profile.

 

[Varulv]

Frank, I keep seeing QB mentioned in other threads. What is it? Sorry, I'm still fairly new.

Quantum board leds. You find them at Horticulture Lighting Group. His advice is basically to get 2 x HLG 360s or build your own.

 

[AlaskaRob]

Sounds complicated. I like simple and versatility.

 

[Varulv]

Sounds complicated. I like simple and versatility.

Not any more complicated than your CMH really.

 

[AlaskaRob]

I'd have to look into it. You may have a point, but I like the PAR (830), CRI (92), Broad spectrum, and energy savings of a 630w. Maybe I'm just stubborn? Lol
LED has great coverage, but the penetration is too shallow for my purposes I think. I'm in a 5x5 tent, and was looking for penetration and simplicity. I really like 2-3 penetration into the canopy. My 6 plants are getting pretty thick, and I would like to keep as much intact as possible once i lollipop everything a few inches below the scrog. Am i wrong?

 

[AlaskaRob]

 

[AlaskaRob]

Previous post was day before. This is from today.

 

[Renfro]

AND you're cheating just a little by using a DE bulb, renfro. lol
Besides, I bet you'll have to change that DE bulb for another bulb spectrum between veg and bloom? Whereas cmh bulb from Phillips can do both.

That room is really just flowering anyways. They are both de bulbs.

 

[Renfro]

My grow is on a little larger scale, for me to really replace HPS with CMH I would need taller ceilings and 1kW CMH, still I wonder about the yields, HPS seems like it can yield more per square foot but I have a lot more experimenting to do on that part. For me it's not about yield per watt but per sqft.

As far as LED penetration goes, my COB setup really puts out intense light and can penetrate, actually have to run it further away than I run HPS. So GOOD LED can penetrate.

Basically if you get good equipment LED, CMH, HPS, MH can all grow well and each has it's advantages. It's up to the grower to determine what is the best fit for their grow. For someone with a 3x3 tent, a 315 CMH is just right. There are LED options that will handle that as well. A 400 watt HPS would handle it. I personally think the disadvantage to LED is it lacks UV. You need a little UV to get max THC production.

 

[Leo_dean]

just want to say a huge thanks to everyone who replied, was not expecting this thread to blow up this much haha heaps of really helpful info guys up to this point I don’t really consider anything other than Leds because I was under the Impression they were the best , im think about growing in about a 3x3 so I might look into 315 cmh (which I have no idea is lol) , Also find I hard to grasp sizes of grow tents coz I’m from Australia so everything’s in metres bit of a pain having to convert everything haha I wanna grow around 5 plants

 

[Frank Cannon]

Frank, I keep seeing QB mentioned in other threads. What is it? Sorry, I'm still fairly new. I just did 6 months of research before making my choices for my setup. I'm going into week 5 of veg after a hiccup with some serious heat issues. Didn't realize my ducting came loose from the exhaust port near window and was recirculating the ambient room air with my tent! Ambient room twmpmoutside of tent is 73, needless to say spikes of 84 scared me a bit and I wanted to give an extra week or two to make sure everything was back inline before flipping the lights for bloom.

The good thing about using the QB96s is Or_Gro has done all the mapping for us and there are some excellent threads which I will post below for you. My advice was to aim for 50w persquare foot which I did and my recommendation is you shoot for similar (lots of people say 30w but I would go higher). So my 4.5 x 4.5 is 20square feet so I ran at 1000w, yes I ran more wattage with more efficient lights than my 600 hps so its not an apples for apples comparison, but the results speak for themselves.

Good luck mate, its difficult to sift through all the conflicting information on RIU! Below is where I gleaned all my knowledge for my first LED grow.....

My thread:
https://www.rollitup.org/t/5-x-5-light-set-up.978296/

Or_Gros mapping:
https://www.rollitup.org/t/qb96-elite-v2-w-sstx-heatsink-question.977654/

A damned good read:
https://www.rollitup.org/t/strip-leds-in-the-garden-of-paradise.954799/

FC
Have a look mate seriously worth a little bit of effort, totally happy with my conversion to QB

 

[Varulv]

just want to say a huge thanks to everyone who replied, was not expecting this thread to blow up this much haha heaps of really helpful info guys up to this point I don’t really consider anything other than Leds because I was under the Impression they were the best , im think about growing in about a 3x3 so I might look into 315 cmh (which I have no idea is lol) , Also find I hard to grasp sizes of grow tents coz I’m from Australia so everything’s in metres bit of a pain having to convert everything haha I wanna grow around 5 plants

1 ft is about 30 cm so that conversion is easy enough.

 

[Varulv]

I'd have to look into it. You may have a point, but I like the PAR (830), CRI (92), Broad spectrum, and energy savings of a 630w. Maybe I'm just stubborn? Lol
LED has great coverage, but the penetration is too shallow for my purposes I think. I'm in a 5x5 tent, and was looking for penetration and simplicity. I really like 2-3 penetration into the canopy. My 6 plants are getting pretty thick, and I would like to keep as much intact as possible once i lollipop everything a few inches below the scrog. Am i wrong?

Im not suggesting you replace your CMH, just answering your question about the QB96.