ÒÒlegilizeitÒÒ
Well-Known Member
Totally right, but the top of the line lights have fairly similar umol/j output, where you can compare them using w/ft.
Obviously these numbers wouldn't be the same for lower efficiency LEDs
300$ light??
- Thread starter Datcoldboi
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Obviously these numbers wouldn't be the same for lower efficiency LEDs
getogrow
Well-Known Member
i have to agree. 500 watts of leds is going to be a constant sunburn. Will be fine with a dimmer but i doubt you would ever turn it up.
That being said i would rather have 500 then the 250 you will be using. So i would buy a 500 and turn it down. way down.
Jimbo the Gael
Well-Known Member
Yes, and it can help op weed out the lower efficiency lights to zero in on the best lights within his budget. The reason I have a problem with watts per square foot is it doesn't take spectrum into account, or active vs passive cooling.
I take your point about comparing lights with similar performance though. I just suspect some of them will be too expensive.
ÒÒlegilizeitÒÒ
Well-Known Member
Sounds like a waste of wattage lol
Veg at lowest setting, then 50-75% in flower? What's the point? Haha
IMO its best to get a light that at 100% power, perfectly illuminates the grow space.
I'd say 300-400w of LED with a dimmer for veg would be more than enough for the OP
jimihendrix1
Well-Known Member
I run a Gavita 1700e. Its no better than my 1000 Hortilux HID that Ive been using for over 20 years. I use the Gavita for veg, in a 4 x 4 area at 24 inches.
I use a 1000w/1700e from Seedlings - flowering. My seedlings never see less than 1000w HID. I grow big plants because of plant limits in an unfriendly state, in 20 gallon containers of Promix BX per plant. No less than 10g. 2-4 plants per light.
I also run DE Gavita 1150w.
Hortilux 1000w HOS is 1600umol.
Gavita 1700e is 1700umol.
Ushio SE 1000w HID is 2100umol, and will do a 5 x 5, but isnt as reliable as the Hortilux.
getogrow
Well-Known Member
There are a lot of variables in this mess. You simply cannot compare a single source light bulb to a nice spread. A 1k hps will grow a 5x5 with no problems but you will have a hot spot in the middle and lower numbers around the edges. So your going to feed them according to the middle ones with the "sunburn". Works out great for us hps guys who are used to it but in real life the difference is stupid. If i wanted to perfect my setup with hps i would have to feed 3 different ratios under the same 5x5 area. (assuming there is no side light or supplemental light)
jimihendrix1
Well-Known Member
Hortilux says a 1000w HPS is good for a 4 x 4 area. Just because it will light a 5 x 5 doesnt make it optimal. Hortilux, and Gavita both say 4 x 4. Gavita says the 1700e is a Direct Replacement for a 1000w HID, in a 4 x 4 area. Not going by my opinion.
getogrow
Well-Known Member
you think im wasteing watts :
I love my led veg lights but gosh damn thats overkill
(its only overkill if its not working) Thats crazy though
getogrow
Well-Known Member
Your opinion holds MUCH m,ore weight around these parts then those specs! your jimmihendrix!
ÒÒlegilizeitÒÒ
Well-Known Member
Well you are wasting electricity in veg for sure unless you have co2
Here is the map for that ligh at 24" (higher than your light)
You are covering your girls in probably over 1000 PPFD of light across that entire 4x4
That is 65 DLI on a 18 hour day. Simple botany says cannabis can't absorb more than 60 DLI at the MAX, with CO2 enrichment. Anything over 45 DLI without CO2 levels at 1200 is completly pointless.
Point of the story, just because you are using an insane amount of wasted electricity, doesn't mean thats normal, or that you should reccomend that to others.
To achieve 45 DLI in veg, all you need is 700 PPFD.
Flower, that is about 1000 (your light is more than anyone should need for flower in a 4x4, even then, CO2 enrichment is almost needed)
jimihendrix1
Well-Known Member
The sun is 125w+ sq/ft at the equator, so I do not feel its a waste of electric ect. They get more than my measly 62w-sq/ft I supply inside. I also run 2x 34w, but run at 40w x Solacure UVA/B bulbs per 4 x 4 area at 24 inches.
Sun is 2600umol, and more if your in the Andes.
I have HUGE airflow. No CO2, but tremendous airflow. Temps around 82f.
Sun is 2600umol, and more if your in the Andes.
I have HUGE airflow. No CO2, but tremendous airflow. Temps around 82f.
getogrow
Well-Known Member
MY point going into this one is that his closet will soon be his bedroom
Jimbo the Gael
Well-Known Member
Where are you getting wattage info for the sun? A watt is a measure of electricity, not light.
Comparing the sun to grow lights isn't really useful unless you're trying to figure out what spectrum to use, or whether to grow outdoors or indoors.
getogrow
Well-Known Member
If your girls are not showing defs then its not "too much". imo
getogrow
Well-Known Member
Comparing the sun to grow lights is exactly what the industry has been doing since we started. Thats how you make a grow light. Study the sun and incorporate that into the design. Its 2021 so we are far past that but not near as far as some think.
ÒÒlegilizeitÒÒ
Well-Known Member
It doesn't really matter what you think.
Google it
Cannabis can't absorb more than around 1000 ppfd in flower, and 700 ppfd in veg
Have you done any research on DLI?
You have to average the suns output at the equator for example. It may be over 2000 ppfd, but it is sometimes cloudy, there is shade from other trees, ext.
The maximum the equator ever sees is 60 DLI
Airflow has nothing to do with co2 enrichment besides giving the plants a fresh supply of whats there. If the room is 500 ppm co2, it doesn't matter how much air flow you have, your limiting factor is still that 500 ppm of co2
Please do some research on the science behind max PPFD in relation to CO2 levels and maximum DLI for cannabis
It will make you a better grower
tkufoS
Well-Known Member
Like "high times"
Doug Dawson
Well-Known Member
You are replacing 1000 watt HID with a 450 watt Spider Farmer? In a 4x4 that only 28 watts per square foot. Don't you feel that is a bit underpowered? I am running 630 watts at full strength in my 4x4 which is what I replaced my 1000 watt HID with. Just curious.
ÒÒlegilizeitÒÒ
Well-Known Member
I disagree.
You give your plants 25 DLI for minimum "optimal" growth.
You give them 45 DLI for maximum "optimal" growth
You can pump it up to 60 DLI, and they may not show adverse reactions, but they still won't grow any faster than at 45 DLI without CO2
All you are doing is using more electricity, for the same output.
Jimbo the Gael
Well-Known Member
That's kind of what I'm saying. Trying to copy the spectrum of the sun is fine, but every time we try to match the intensity we end up with crispy plants.