Lighting Watts per square foot.

[Discretepete2676]

Was hoping to get this thread going for newbies like me trying to take our learning a step further. Upon reading I keep coming across watts per square foot....but I'm not sure how its measured really and for example with led which number do I go by? The actual watts drawn or the number they use for sales? Lol as a newbie I decided ask Google first. I went and found a calculator and typed in some numbers and I think I missed something somewhere. ...I have a 2x4x6 grow space. I believe equivalent to 58 square. In order for me to have 55w per square u would need 2 1600 watt lights. Am I missing something here? Lol are we only supposed to measure floor space the light is covering? For example my 2x4 tent I would count as only 8 square feet for measuring purposes? It would seem more logical I guess because 1 400w light creates exactly 50w per square if you plan on only covering the 8 square as discussed above. Any thoughts on this would b super helpful for me and other newcomers. Thanks ahead everyone.

 

[Weedman30]

Hey man check the reply in other Thread.

As for measuring sqft it's canopy sq ft so yes the ground space 2x4 tent is 8sqft

As for watts go off the Actual draw rather then what they sell it at. It's normally about half of what the advertise.

 

[TheSpacePope]

Agreed as above. You measure for light footprint, the volume you use for your fan.
Rule of thumb 40-50w per square foot is good. But I went the other way instead of 2 large plants for 7-8oz In a 2x4. I went for lower watts 250 and squeeze 3 in for about the same yield but more variety.
3-400watts would be ideal in that size tent.



I use 5gals BTW if that matters

-TheSpacePope

 

[Discretepete2676]

Well on the fly I grabbed a Mars 2 1200 watt last night. I plan on upgrading to a 4x4 tent after this next run and doing perpetual grows starting 3to4 plants every forty days. I'll need to get an led or two just for the veg side of my tent as the 1200 will b for flower. But for my next run I'm starting tomorrow will b 400w has for the first few days until the led gets here, ordered last night, then I'll b putting that in for the grow. After preparing my puts and sitting them in my tent and then waiting for brands to pop, light should b here b then hopefully. What would u recommend for a veg light for a 2x4 space. 3 to 4 plants. I use 3gal pots

 

[TheSpacePope]

Damn that is a very similar concept I'm doing now. I'm running a 2x4 now but planning on a 4x4 as well . But I am pretty sure I'm doing a platinum p600 or p900 on one side and ms004s on veg on there other side and doing a perpetual as well. An just shift them over as I harvest vs trying to meddle with coverage later on with a single square light. An keep it all contained in the 4x4 and keep my legal plant count.

 

[Discretepete2676]

Yup that's about where in at too. After this run of auto triangle kush, if all goes well I'll b trying to run multiple strains so I have different smoke around instead of just a bunch of one kind. Besides learning how to use led and my new nutrient line I'll also b working on giving my girls more individual attention as they do grow different even within the same strain. How are the platinum p series? Have you used them before?

 

[TheSpacePope]

Haven't used them before but their specs are pretty good and price is on part with Mars and grow button or bloom. but they have a rep of standing by their lights everywhere I've seen and hard to find a bad review outside of their Coverage discrepancy but that is the norm in Leds. but very good if you actually know coverage(realistic) like running 2 p600s for a 4x4 =690-700w with dense coverage cuz they are long rectangular. Instead of square and have plants at the edge leaning towards the center. An they post all their par stuff. 12 light bands and 90day no problem $$ return and 5 year warranty. Which is better than the more expensive diamond led lights with the same stats. But time will tell for me.

I was gonna grab the HS1s from Grow Northern. But the fact that they have been telling me for nearly 18months they don't know when a USA version is coming, really left a bad taste in my mouth considering we own the legalization movement. No US love no GN love I have 2 ms004s for the record

 

[Discretepete2676]

I almost bought the new Mars pro epistar160 fix I liked the rectangle structure but I needed a single light or two lights that were very close to my 600hps 1200 was my best choice for a starter light. Probably run like 2 400w for veg when I upgrade tent

 

[IndyLED]

Was hoping to get this thread going for newbies like me trying to take our learning a step further. Upon reading I keep coming across watts per square foot....but I'm not sure how its measured really and for example with led which number do I go by? The actual watts drawn or the number they use for sales? Lol as a newbie I decided ask Google first. I went and found a calculator and typed in some numbers and I think I missed something somewhere. ...I have a 2x4x6 grow space. I believe equivalent to 58 square. In order for me to have 55w per square u would need 2 1600 watt lights. Am I missing something here? Lol are we only supposed to measure floor space the light is covering? For example my 2x4 tent I would count as only 8 square feet for measuring purposes? It would seem more logical I guess because 1 400w light creates exactly 50w per square if you plan on only covering the 8 square as discussed above. Any thoughts on this would b super helpful for me and other newcomers. Thanks ahead everyone.

2x4 =8square ft and wattage isn't a good baseline to go by,but being new it is the easiest to understand. wattage needed will change depending on the LED fixture your using.
480watts Vero29 4000K or 400watts CXB3590 4000k
3000 is flower and 4000K for the cycle.
Mono based Cree XT/XP 450watts will get ya there
If ya have any questions just ask.

 

[IndyLED]

2x4 =8square ft and wattage isn't a good baseline to go by,but being new it is the easiest to understand. wattage needed will change depending on the LED fixture your using.
480watts Vero29 4000K or 400watts CXB3590 4000k
3000 is flower and 4000K for the cycle.
Mono based Cree XT/XP 450watts will get ya there
If ya have any questions just ask.

I would buy 2 smaller fixture for output control