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led question

B

baddagger

Member
hey all im in the process of doing my research before I start building my grow room. And I have had read about people using led light for the grow. I have read that a lead lights puts out more useable light then what a hid light puts out is this true?

Now how would I go about to try and figure out what how many and how strong of lighs I would need? I was plan on doing a grow tent 4x8x8 for flowering and also for a vegging tent. Each tent would have 8 plants
 
exploziv

exploziv

pure dynamite
Administrator
Veteran
It's true that leds put out more usable light for the plants, and they also run a bit cooler, so yes.. you can yeld the same as hps. I'd go with about the same power as I would use hids at, maybe just a bit under like 3/4 of the hid power. never trust when they say leds replace 3-4 times more hid power at same wattage.
I found that supplementing the leds with t5's or other floros on the sides does wonders. Do a lot of reading before deciding on the final set-up. Also, you can consider DIY if you have some skills at that. Lots of info on that too around the forum.
 
B

baddagger

Member
exploziv_gbb said:
It's true that leds put out more usable light for the plants, and they also run a bit cooler, so yes.. you can yeld the same as hps. I'd go with about the same power as I would use hids at, maybe just a bit under like 3/4 of the hid power. never trust when they say leds replace 3-4 times more hid power at same wattage.
I found that supplementing the leds with t5's or other floros on the sides does wonders. Do a lot of reading before deciding on the final set-up. Also, you can consider DIY if you have some skills at that. Lots of info on that too around the forum.
Click to expand...


well im still trying to figure out if I want to go with hid or led. I know that led lighting will cost more for the start up but I don't mind spending it if I can get more yield in the end and better quality crop.
 
exploziv

exploziv

pure dynamite
Administrator
Veteran
I've seen better quality from my garden since I started using leds, it may be because of the lower temps or because of the led lights, or it may be both. Anyway, I'm happy with that and now I can grow all summer and not have worries.
If you're after yeld you also need to consider going vertical. Dunno if that is doable with just 4 feet on a side, but if you get a bigger tent that could work better than leds for you, with a smaller initial investment.
 
Big Sky

Big Sky

Member
A combination of LED and HPS is great but if you can go full LED its worth the investment-
no ballast, no bulb changes year after year, your looking at a 50,000 hour + lighting fixture-
The technology and understanding of light spectrum and LED growing have moved along well enough to make the investment in my opinion-
I'd have to agree with explosive:
there are a lot of claims out there.
You just have to A. make an informative decision when buying LED
B. Find that product at a good price but get quality built stuff!

LED will save you loads of heat buildup, cleaning(hoods/glass/fans etc), power, etc-
way less environmental impact-

THe initial costs are a little high but when you take a 600w hps for example
quantum ballast around 150+
good air cooled hood can run up the same 150-
the larger fans to cool the grows $$$
70-100$ bulbs, thats per fixture once a year (for quality agro bulbs)
your saving almost 1000$ in just bulbs over a 10 year period (the life of a quality LED panel )
so to me the investments are well worth it-
 
B

baddagger

Member
by any chance would you know of any good reads/post on led lights that would break down what I need to know so I can make a informed judgement on what type of led to buy and how powerfull?

I am trying to get my caregivers card so that's why im getting into this but my big thing is I want to be able to try to yield 4oz range per a plant if I can get more then deffently want to.. and I know that I need enoff light to so the plants can grow enoff bud, but can producing that much yield per a plant be done with led lights?
 
Desert Hydro

Desert Hydro

Well-known member
Veteran
youre gonna need a lot of LED lighting for that sort of output i would think. i may be wrong. IDK, im waiting on my first units to arrive and test. out. im gonna run 2 300W units in a 2x4 tent. i think with my AK cut i have and a SOG i can do a LB for sure in that tent. only time will tell. my first log will go up as soon as my lights come in. the plants were vegged under t5's and they have been under 300w hps for a few days while i wait on my LED's
 
tenthirty

tenthirty

Member
well here is a thought, would a mix of both hid and led work better then just hid?
Click to expand...
https://www.icmag.com/ic/showpost.php?p=5522823&postcount=4475

by any chance would you know of any good reads/post on led lights that would break down what I need to know so I can make a informed judgement on what type of led to buy and how powerfull?
Click to expand...

Read, read some more............Read till your eyes bleed and your brain explodes.
Read the stickies at the top of this forum.

I want to be able to try to yield 4oz range per a plant
Click to expand...
It's not the amount of light per se, but the quality of the grower.

In my experience, it's taken me 9 runs of the same strain and same room to get dialed in enough to get 1g a watt, while lowering the total wattage of the room from 1k HPS to just over 600w of hybrid and have increased the harvest quality and quantity almost every time.

With a question like that, it is my opinion that it would be well advised to concentrate on not killing the plants before shooting for any weight goals.

Did I mention read.
 
B

baddagger

Member
tenthirty said:
https://www.icmag.com/ic/showpost.php?p=5522823&postcount=4475



Read, read some more............Read till your eyes bleed and your brain explodes.
Read the stickies at the top of this forum.


It's not the amount of light per se, but the quality of the grower.

In my experience, it's taken me 9 runs of the same strain and same room to get dialed in enough to get 1g a watt, while lowering the total wattage of the room from 1k HPS to just over 600w of hybrid and have increased the harvest quality and quantity almost every time.

With a question like that, it is my opinion that it would be well advised to concentrate on not killing the plants before shooting for any weight goals.

Did I mention read.
Click to expand...


I do understand that I need to learn how to grow and I wont get top yield at first. But also if I need say x amount of lighting to produce 1 pound of buds and I only have half that amount of lighting then I wont be able to get to that point even after learning the ropes right?

So what im trying to do is get my self set up with all the right amount of lighting and equipment I need so I can get to that point once I have the experience under my belt.
 
B

baddagger

Member
oh and I have been reading a shit load. My eyes and brain both feel like they are going to explode. Ive just read the marijuana horticulture book.
 
tenthirty

tenthirty

Member
Well, space dictates everything.
The size and location of the grow will dictate the limitations for lighting as well as ventilation.
Ventilation is a close second.
(I could say environmental control, but lions and tigers and bears...oh my!)

Knowing the right question to ask is 90% of the battle.
If you know your square footage, 30 to 50 watts a sq ft.
50 more or less for HPS and closer to 30 for led or CMH.

Your tent running 1k of any light will do a +8f. over ambient with 8" fan such as this.
http://www.plantlightinghydroponics.com/active-air-720-cfm-inline-duct-fan-p-2756.html

So the real question is, how much light can I cool.
Depending on where you are and how much you are willing to spend on AC or heat, will have an impact on your choices.
 
BrownThumb

BrownThumb

Member
LED's get hot, so ventilation is a big deal as you ramp up your wattage. It's less of an issue if you can keep your grow short as hot air rises and the more headroom you have, the cooler the light will stay.

If you're doing 6 sf you will need at least two lights to really cover the area as LED's main power is straight down. The design of your LED will dictate which are best to run with. I went cheap and got a 600 watt (really about 350-384 range) Chinese made South Korean LED through LG on Alibaba. Paid about 575 to have it delivered from china. It already had a PSU fail, but that was due to heat and also showed that they have excellent product support to go along with the 3 yr warranty. These don't have heat sinks, so really, don't go there if you can't keep the unit cool, but that's where the deals are to be had and the lights work really well, IMHO. I also have a Blackstar 180 that just took a shit on me that I have been using as supplemental lighting. In fact, that light works very well for a 1.5 sf area, however I am having to go through more expense and trouble to get the issue resolved w/ that company, and they are in the US reselling Chinese made wares.

So here's the deal, I am in a closet with a space of about 23"*30", so let's call it 2 sf or 4 ft total. My light, which is 18.75"*22" doesn't fully cover that space (unless I raise the light higher than I want) IMO, and I don't think anyone is going to say that I am not giving them enough watts (384/4=96 watts psf). Some would say I am a fool and they would be right, but the fact remains that the footprint of LED's is roughly that of the chassis and not much more. That 384 watts heats up my closet like an oven unless I leave the door open. There's more space in the closet than the space I can light, so if the space was smaller I bet it would get to be over 100 F. You either need to keep them in an open space or in a space with good circulation as LED's suck in their own exhaust, if you dig.

You can get some better quality LED's, some are way better, but you will pay a fortune in comparison to the Chinese route and the difference in results can't justify the cost differential, IMO.

So, if you get a couple of smaller wattage units, that would probably serve you well and you will begin to feature insanely dense plants. Do at least 50 watts psf if you end up going LED, unless you build your own and know you can go less and get the results you want. LG has cheaper lights if you look around their presence on Alibaba. Some that have free shipping, but some of them look too cheesy and outdated to me. This is the first one (lgledsolutions.en.alibaba.com/product/731223410-213321803/hydroponic.html?tracelog=cgsotherproduct1) I was looking at so you can get an idea of what I went with, specs, etc. I actually went with the extra large, not this one, but they offer different shapes in the line I chose which is really helpful. No, I don't work for them or own stock, just sharing. Look around though and see what's out there that has your desired spectrum, wattage and price range, that's how you'll figure out if LED or HID is the way to go. Last thought, I am not yet totally convinced LED can outperform HID in yield, but then again I have never grown w/ HID, just seen the results.
 
B

baddagger

Member
ok so here is the break down of what I am planning on doing for a grow space. I have a 11foot x 20foot that is 8feet high. that in a basement

I am planning on using two grow tents that are 4x8x7 or 4x8x8 in there. And what I was planning to do was set it up so that will rotate 4 plants every month(4 set in all). So one tent will be for flowering that will have two sets of flowering plant .and one tent for vegging that has two sets of 4.

Now I do know that in the flowering stage they can take longer then two months and will adjust to what they need. im just trying to use theis 4 month cycle rotate as a base line.

I was figuring to use two 600 watt hid lights in each tent. So each set of plants(4 per a set) would have its own 600 watt light. Was going to use mh in the veg tent and hps in flowering tent. But now im not sure if I want to go with hid light or led. to many damn options lol.

Also a nother thing that im consdeing doing was to use co2 from a tank to help speed up growth. Now would co2 work better with led or hid? and what I mean by that is I know that I have to cycle the air to help control the heat. But if im always cycling the air all the time wouldn't it make it hard to keep the co2 ppm in the 1300-1500 range?

So i was guessing that if i used led then would have less heat build up then i could set a timer to turn on the inline fan once every 1.5 to 2 hours to romove the heated air and then set a timer so that the co2 tank regulator would bring the ppm back up to were i have it set.
 
W

WeedIsGod

Member
If your cool tube is enclosed (i.e. not passively taking in air from the grow room, but rather, taking in air from a duct that leads out side, or...) you can keep the co2 levels high w/o much worry about pumping it out. The heat that escapes the cool tube should keep the room temp about where you want it, but if things get out of control you could use an AC unit.

With co2 supplement you don't need to circulate outside air into the tent much because the whole point of that is to draw in fresh co2 rich air to your plants.

RH can be higher with increased co2, but if things get out of control you might think about a dehumidifier.

I think LED and HID perform about equal in regards to co2 supplement.
 
B

baddagger

Member
WeedIsGod said:
If your cool tube is enclosed (i.e. not passively taking in air from the grow room, but rather, taking in air from a duct that leads out side, or...) you can keep the co2 levels high w/o much worry about pumping it out. The heat that escapes the cool tube should keep the room temp about where you want it, but if things get out of control you could use an AC unit.

With co2 supplement you don't need to circulate outside air into the tent much because the whole point of that is to draw in fresh co2 rich air to your plants.

RH can be higher with increased co2, but if things get out of control you might think about a dehumidifier.

I think LED and HID perform about equal in regards to co2 supplement.
Click to expand...


ok so I was not to use co2 supplement, how much air exchanging do I need to do with a inline fan to be able to give the grow room enoff co2 to get the extra growth speed like I was using co2 supplement?
 
W

WeedIsGod

Member
co2 supplement done correctly will grow more vigorously than simple air circulation, although it can be quite expensive. Many people grow very happily w/o co2 supplementation.

Rule of thumb:
Exchange your grow tent's entire internal volume at least once every 5 minutes.
4'x8'x8'=256ft^3
256ft^3 / 5 minutes = 51.2 cubic feet per minute (cfm)
That is your minimum. Some people say once every minute (probably a lot, but okay), so I'll say 250cfm is your maximum. Anything in between those two numbers that sufficiently cools your light or room sounds good to me.

General note: After you add filters your cfm goes down. The longer and smaller in diameter the air duct your draw from/push through gets the lower your cfm gets.
 
medmaker420

medmaker420

The Aardvarks LED Grow Show
Veteran
If you are new to growing I would try all sorts of lighting options but hps and led are both relevant in 2013 including during flowering.
 
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