# LED instead of HPS ?!



## Mart17 (Jun 26, 2015)

Hey everyone!

I have to say its nice to been here again in this forum.
I learned growing MJ 4-5 years ago from this forum. So first of all i wanna say hello for my buddy Hushpuppy, i hope hes alright in these days.

Today now im an experienced grower with a lot of successfull grow behind me.

Lately though i have some problems with the heat/CO2/Air circulation.

Since i cant install a split a/c unit and in europe i cant find a dual hose mobile a/c. I have to figure out what should i do with the Co2 that is blowing out becouse of the portable a/c unit in summers.

And here comes the LED light.
I did some research about it and i have to say that LED lights are developing and evolve so nice and quickly that maybe soon its time to slowly exchange my HPS to LED's.

I created this topic becouse im curious about some people's opinion about this good technology. Hushpuppy, THG, Rosebud, Hamster and other experienced people  

I know back in the days THG's opinion was that LED lights are not good enough and everyone agreed, also me.

But now with the 3w and the 5w diodes comming out maybe there is time to think about it.

I have a 4mx5m room with good height.
4x 600w hps
Soil grow
White Russian

Im seriously thinking abut slowly replacing my HPS light systems to LED grow lights.

I think the best ones are the 5w diode ones but i dont know wich brand is the best for successful flowering.

I did some research about the Mars 2 led and with the 1200w(input 600w)
or 1600w(750w) several grower did a really good run with high yields.

I dont want to save electricity...just want to normalize heat in the summers and want to use the advantages of this modern led system.

Ive read that the 1200w and 1600w also doing heat but i assume its far not that hot as a 600w hps.

I really want to hear your opinion guys about this Mars 2 led light . I know it comes from china but a lot of peaple claim that its made from good material.
It has 5w diodes in it so it could be a replacement for the HPS.
Also it has a 3 year warranty.


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## yooper420 (Jun 26, 2015)

Have not saw Hushpuppy on this forum since I joined almost a year ago. He was on 420 mag when we all left.


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## Mart17 (Jun 26, 2015)

Ah im sad to hear that.


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## Rosebud (Jun 26, 2015)

Hushpuppy is here, just maybe not feeling well at the moment. Sending healing mojo Hush.

Welcome back Mart!  Led's are much much cooler running. Mine in the shed run less then 10 degrees above the ambient temp. I like mine. I don't know if I get the same weight in the end or not. I need to grow more under them than I have. Hamster is putting out the dank with them too, I bet he will stop by.

THG has got her feet wet too. Her computer is down today, but she will catch up with you.


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## techrons78 (Jun 26, 2015)

Mart17 said:


> Hey everyone!
> 
> I have to say its nice to been here again in this forum.
> I learned growing MJ 4-5 years ago from this forum. So first of all i wanna say hello for my buddy Hushpuppy, i hope hes alright in these days.
> ...



 Ok so you say led or hps but you dont want any opionions abiut the lights you are using...well I guess maybe you at an expert grower but not at led?...I dont knock any company im just waiting for about a, year or 2 see how long these mars lights last...soo good luck to you sir..


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## Mart17 (Jun 26, 2015)

Hey Rosebud!

Much cooler?! Thats a nice thing to hear....in summer im having a hard time maintaining my CO2 system.

Well techtrones to be honest im not in a hurry...My HPS setup doing a really good work.
But im kinda modern guy and personally i really like the led's evolving.
Soon we will switch our hps systems to leds for sure.


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## techrons78 (Jun 26, 2015)

Mart17 said:


> Hey Rosebud!
> 
> Much cooler?! Thats a nice thing to hear....in summer im having a hard time maintaining my CO2 system.
> 
> ...



You will love them. .I do....


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## Locked (Jun 26, 2015)

I have been running all LED lights in my Flower Tent now for many months. Made the switch from HPS and am not looking back. I have one unit from TopLed and One custom unit that PJ had made.  Love them both.


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## Dr. Green Fang (Jun 26, 2015)

All LED for awhile now. Will never go back :aok:


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## Kraven (Jun 26, 2015)

Yea hammy I want to get my hands on a PJX180 or two myself


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## Locked (Jun 26, 2015)

Kravenhead said:


> Yea hammy I want to get my hands on a PJX180 or two myself



I have the PJX 360. I dig it.


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## yooper420 (Jun 26, 2015)

Been using my LED`s for 3 years or so, on almost constantly. Very happy with them, but always room for improvement. Have the real Advanced Diamond Series 300`s x 3, not the knockoff`s on flea bay.


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## The Hemp Goddess (Jun 27, 2015)

Like mentioned, I am just getting my feet wet.  IMO, a few years back LEDs were not up to par, they cost so much, and were so overhyped that no one could count on reliable information from the manufacturers.  They get better and cheaper all the time, but are still quite expensive.  I am on my first run and so, with this LED stuff, I am a newby, too.

First I can say that while they run cooler, they still put out a lot of heat.  And they are still expensive.  I got a lot of conflicting information in my search for knowledge, so am kind of figuring that I am going to have to discover at least some of this on own.  One of the things I have learned is that the LEDs are pretty directional and do not have a large footprint like HIDs.  Because if this, it is often better to buy more smaller fixtures than 1 or 2 larger ones.  

While you are supposed to be able to use 50% of the wattage with LEDs that you had with HIDs, I am replacing a 1000W HPS light with approx. 700w of LEDs (actual draw).  I purchased a Mars II 700W that pulls around 330W.  I am also using a light that someone loaned to me, an Apollo Purple Sun 768W that pulls about 370W.  They are different types of LEDs.  The Apollo is a cob and you are familiar with Mars II.  Heat tests I have done show me that the Mar II runs hotter than the Apollo.  Running the lights at night, I am able to keep the upper temps in the closet in the mid 70s.   We have a blistering long heat wave coming--about 2 weeks with temps at 100 or higher every day....we will see how we do.  I was worried that the LEDs may not put out enough heat for winter growing, but they do not run as cool as we are led to believe.

Coverage areas was where I seemed to get a lot of conflicting advise.  The number of 60 _working watts_ per ft was kicked around, but also the "you can run 50% as many watts" as you had HIDs.  So, since many of use only run 60W or so of HPS light, running 60W of LED would not be cutting my wattage.  I had ordered a 3 x 5 tent for this project, but it ended up being a 5 x 5 tent that was just too large for the space I had planned, so I went back to my original flowering closet, which is 3 x 6.5.  

It is still quite expensive to go with LEDs. You can get a Mars II 700W for just under $300.  I think the Apollo runs around $400.  So, I am using about $700 worth of LED light to replace a 1000w HPS that cost under $200.  And LED technology keeps improving at a fast rate.  

I believe that I may live to see the repeal of the cannabis laws, something I have hoped for since the 70s.  And because of the changing laws, I think that manufacturers are scrambling to produce better cheaper lighting as there will be a large demand for it.  Oregon's recreational law, which goes into effect July 1, allows 4 plants per household.  Not a lot, but jeez, what a step forward!


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## yooper420 (Jun 27, 2015)

Yes, I too am believing that we will live to see cannabis free and legal to all. At 67 years old, it`s about time, but hurry up, some of us old farts ain`t got a lotta time left in the vertical position. 
FREE THE WEED.


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## Kraven (Jun 27, 2015)

Yup, it's gonna happen. THG I'll be swinging LED's at some point, so watching to see your grow, hope you like them. When the time comes I'll go with a little higher end fixture, but only when I feel like the return will be worth my investment. The MARS are good lights, they should do well.


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## yooper420 (Jun 27, 2015)

Return on investment ? Not having to buy any MJ for 3 years, think I`m on the plus side now.


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## Kraven (Jun 28, 2015)

lol yea yoop, thats the truth. These are the ones I want yoop, still a bit pricey but if I'm gonna go LED this would be how I would want to roll.

http://www.bmlhorticulture.com/spydr-600-start-max-spectrum/


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## yooper420 (Jun 28, 2015)

The BML Spydr`s look great. I checked `em out, really like `em, but the cost is prohibited on my wallet. Luv `em, just can`t afford `em. Next up is another DS 300, will buy on Veteran`s Day, cheapest price all year for veterans.


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## Dr. Green Fang (Jun 28, 2015)

I'm so impressed by my Mars lights... I didn't think they would work as good as they do. I can't wait to get entirely dialed in and really see what they can do!


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## Mart17 (Jun 29, 2015)

Thank you everyone for the replies.
It was really useful. 

Im really sad that here in middle europe politicans and the people really dumb and stupid.
The law is very harsh against MJ growers so as with the users. Would be really happy if they would have just realize that mj needs to be categorized to a different type of drug ...near to the alcohol. But i think thats not going to happen in the near future. Maybe when USA changing a lot Europe will too.

This mars led is quite good it seems but still i will wait a little to see how this tech will improve in the near future.

I need to re configure my whole electricity plans for my room if i wanna chang to led. 

My main goal is to replace my 4x 600w hps to leds. Im using adjust a-wings reflector so im a bit worried about the leds light coverage. Im having quite a good harvest with my setup in winter but in summer im having a hard time.

How many led do i need to replace my 4x600w hps?! I have to say that my wattage shouldnt outrun 600w/ fixture (input) becouse this is the maximum i can use. My electricity is limited.

Becouse of the co2 the only good method is the dual hose mobile air conditioner for cooling right?! I cant menage to build a split air conditioner becouse of safety. I can only use mobile air conditioner wich can be put inside and not having an outside unit.

If i cant menage this i will change to my lights to leds so can control the heat much more in summers.

How many time a LED fixture cooler than HPS 600w? The equal version?!(2x700w led?!)
A 600w hps equals 1x 1200w 5wdiodes led or 2x 700w led?!

If i get a light mover 1 bigger led panel can menage the light right?! The area if wich it needs to be covered is like 5 foot x 6.5foot (1.5m x 2m). I can menage to grow this space with my 1x 600w hps with adjust a wings. The outer ring of  plants are not that strong as inner ones but i have decent yields and im using 4x600whps close to each other so i can grow like 60 plants in sog method.


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## Dr. Green Fang (Jun 29, 2015)

> My main goal is to replace my 4x 600w hps to leds.



Interesting. I changed my 4x 600w hps for 8x Mars II 400w LED's. 



> I have to say that my wattage shouldnt outrun 600w/ fixture (input) becouse this is the maximum i can use. My electricity is limited.



Put it this way. A direct replacement to a 600w hps is a 300w ACTUAL DRAW led fixture. Basically, two of the Mars II 400's or 1 of the 700's BUT... with a larger footprint you want MORE of the SMALLER fixtures for a plethora of reasons. So, I had two 4.5' x 4.5' tents that each has 2x 600w hps inside. I directly replaced those for 4x Mars II 400's. My electricity bill has been HALVED. Yes, you read that right.. HALF! My nutrient bill is also half, as they take roughly 1/2 the nutes required than with HPS as the LED spectrum actively "feeds" the plant  Also, I don't have to run my vortex fans nearly as fast, so you save money there as well. 



> If i get a light mover 1 bigger led panel can menage the light right?



Bad idea. If your one 1200w fixture breaks, you're screwed... but if you have 4x 400's, and one breaks... you're quite fine until you get sorted! Also, you have a WAY more versatile foot print with 4x fixtures. Say you have a 1/4 of your tent that's about 15" tall, and the other 3/4 of your tent is 36" tall... well, adjust 3 lights to the 36" ones and then adjust the one light to the 15" one. :aok: Also, you get "overlapping footprints" with multiple fixtures.


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## The Hemp Goddess (Jun 29, 2015)

I do not like light movers.  Have 2 of them gathering dust.  IMO, one of the biggest mistake growers make is trying to make their lights do too much.  You are far better off making your space smaller rather than trying to stretch the lights to cover too much area.    

While with HPS larger fixtures are generally better, with LEDs this is not true.  I opted for the 700W and the 768W because my space is rectangular--3 x 6.5.  Two of the Mars II 700 will run over 600W actual wattage, but then so does your 600W HPS.  You say that your electricity is limited....what exactly does that mean?  Do you not have the amperage or is the cost a concern?  

The LEDs do not run as cool as I had hoped.  The Mars II runs hotter than the Apollo Purple Sun, even though the Apollo is larger.  I had my HPS hood air cooled, pulling cool air from the crawl and ran the lights at night and did not have much problem keeping it cool.  Temps are only running a few degrees cooler than my HPS with an air cooled hood.

I am not running 50 of what I was, so my electricity bill will not be cut in half.  I am running about 70%, the Vortex is running at full speed...but it was 108 yesterday.  So, while I will see some electricity savings it won't be huge.  Frankly, I was really hoping they ran cooler than they do.  And I will reserve judgment until I have run a few crops.  There is more to it than just changing the lights.  I expect a learning curve with the LEDs.


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## Mart17 (Jun 29, 2015)

Thanks for the info Green Fang!

So basically you saying that a 600w hps can be replaced with 2 mars 400 or one 700...that would be really cool...a mars II 400w actually use 150-200 watt input power per fixture. 
It means i can run 2x of that fixture wich use max. 400w. That would be super cool.

I thought a 600w hps equals a 1200w mars II led wich uses 590w input power.

Basically i have 4x600w input power i can use for light in that room. It means i have around 2.5KW in that room for the light. So for maximum efficiency i want to use nearly all that wattage. 

yes the light mover idea is probably not good im understand what you are saying.

Also i have to say im not using tent. My plants are in a big room in 2 lines.
The lines are 13foot x 6.5 foot. 1 line is lighted by 2 600w hps adjust a wings contains 30 plants sog.
Somehow i have to menage the led lights right to be able to feed my girls good enough with light. I have to change my pattern.

Another question just for sure. If i replace 1x 600w hps for 2 700w marsII means i will have a light intensity like i would have a 1000w hps or a little more but on the same wattage as a 600w hps. MAn that would be awesome.


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## Mart17 (Jun 29, 2015)

Hey THG!

My power is limited means i have 16 amper hubs or what it called in english.
I have 1 big room and 1 small room for flowering and 1 medium room for the babies and for the mother plants.

In the big room i have several fans and a portable ac unit. The small room is a basement. There im not using co 2 just a vortex and 2x 600w hps with some oscillating fans. Also im using a fountain where my water from and im using a pump.

So this all means im nearly hitting the limits of my electrical usage in there. Thats why i have to calculate carefully becouse if im hitting the limit the power snaps down and thats rteally bad for me in mid summer.


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## Mart17 (Jun 29, 2015)

Im really curious about how would the temp drop down in the main big room if i would change my hps lights with leds...maybe my portable ac wont work that hard in that way so my co2 would stay in there much much longer and in that case i dont have to buy a lot of co2 tanks in summer. Damn i really need a dual hose portable ac 

I know that maybe im having a little bit too much plants for my lights..but i want to produce the highest possible yield my room and electricity can handle. I wish i could put in 2 more 600w hps but simply i cant...
But with leds maybe i can.

Also i wanna say that i do not have my lights air cooled. 
So that would be a huge difference in temperature?!


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## The Hemp Goddess (Jun 29, 2015)

My temps only dropped a couple of degrees.  Other than removing the ducting from the hood, I made no changes in my ventilation and they simply are not running that much cooler.  I am a little confused when you start talking about your ventilation and cooling....what does an A/C have to do with buying CO2 tanks? Tell us about how your rooms and the ventilation is set up....I am confused.  Do you have an exhaust system set up that exchanges the air in your space at least once every minute or 2?

IMO, it is detrimental to yield rather than beneficial to try and make your lights cover more area than they should.  In other words you can end up with less bud and it is lighter and airier than bud that has adequate light.  Tell us the room sizes and we will tell you how much light you need.  You are far better off making your space smaller than trying to make your lights go further than they are meant to.  

Is your power 120 or 240?

While technically, a 1200W LED does use about the same amount of electricity as a 600W HPS, the premise is that we can replace an HPS with an LED than runs at 50% of the wattage the HPS did.   So, theoretically a 600W HPS can be replaced with an LED that draws 300 or so watts.


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## yooper420 (Jun 29, 2015)

Huh ? As I scratch my head in confusion. Lost in translation I think.


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## Mart17 (Jun 29, 2015)

Okay ill try to explain. 

My big main flowering room size is 16 foot x 13 foot.

There im flowering 60 plants.

Since the 4x 600w hps is really hot and im using co2 i have to cool the air down somehow thats why im using a portable ac single hose equipment.
With signle hose unit the main problem is that it brings air out from the room when chilling. Im enriching the rooms air with co2 so that co2 also been ventillated outside with the hot air. Thats why i need a dual hose equipment becouse that ac unit uses outside air to cool the inside temp and not bringing co 2 out from the room.

Well it also bring outside air in and mixing it with co2 enriched air but its much more better than a single hose unit.

I have a co2 system and im trying to menage 1200ppm co2 concentration in the room when lights are on.
In summers becouse of the single hose ac unit a lot of co2 getting out from the room so i have to buy several co2 tanks to keep my room co2 concentration at 1200ppm.

My room setup is quite simple im having 4x 600w hps. 2 line of plants. 1 line contains 30 plants quite a bit of lollypoped under 2x 600w hps. the 2 adjust a wing can cover most of the area in 1 line but some plants are a bit weaker than in the middle ones ofc.

My air movement is quite good. im using 4 oscillating fans. 1 floor oscillating fan wich blow co2 up from the floor(we know co2 heavier than oxigen, thats why) 2 side fan wich  blow each line of plants from the sides and one  big fan wich blows all the 2 line in front.

Well maybe im not saying it clear but i have to say that the air movement is quite good.

My only problem is that i want an air sealed room so i can maintain 1200-1500ppm co2 constantly for my plants when lights are on.

My main goal is to produce 2-2,5 kg each run from these plants. In winter i can do this but in summers i cant.


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## Mart17 (Jun 29, 2015)

sorry my english is not good in these days...i forgot a lot. 
I hope you guys can understand what im writing more or less


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## yooper420 (Jun 29, 2015)

Your English is good enough, gotta admit what you are asking is over my head. I know someone here will be able to help, just not me. Sorry.


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## Mart17 (Jun 29, 2015)

I forgot to mention that my electricity is 220v
Just to answer THG's question 
Not the money the amper is the concern.


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## next (Jun 29, 2015)

"My only problem is that i want an air sealed room so i can maintain 1200-1500ppm co2 constantly for my plants when lights are on."

I think the only way to do that is with sealed, air cooled hoods, to dissipate the heat from the light, without removing air from inside the tent. Don't think u can pull it off with LED's.


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## Mart17 (Jun 30, 2015)

Yep i tried that. I had a really hard time with the ducting and imo for my project air cooled hoods not really an option. Well maybe with some changes and if i replace my adjust a wings i could do it..but im affraid i would loose a lot from the yield.
 Im not using a tent. I flower my plants in a big room.

At the moment i can only do the light coverage what i want with my adjust a wings reflector.

THG said shes temp dropped a little whith leds. Shes having air cooled hps. My hps light dont have any heat protection. So if i switch to led it should be a huge diffrerence. Also thats not a problem if my ac re change my air inside the room 1-2 times in an hour. Just dont do it constantly like now.


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## The Hemp Goddess (Jun 30, 2015)

The reason that you are not having heat problems is that you are way way underlit.  For a space as large as you have, you should have a _minimum_ of 12 600W lights to be adequately lit (5000 lumens per sq ft).  I had 1000W in a space that is 3 x 6.5 or 19.5 sq ft.  You are running 2400W in 205 sq ft.  

You must have some heat problems if you say you can produce 2-2.5 kilos in the winter, but not in the summer.  If this was my grow, I would get air cooled hoods.  This way you can cool the lights themselves without exhausting the CO2 out of the room.  But you will need an adequate ventilation system set up with a centrifuge type fan like a Vortex.  Why do you think they would affect yield?  I would also recommend that you get your space a lot smaller and start growing fewer plants.  I cannot imagine what it must cost to get CO2 levels to 1200 in a space as large as you are using.  That has to cost you a huge amount and it could be cut by 75% if you gfot your room to the size it should be for the lights you are running.

It is a misconception to believe that more plants equals more yield.  It oftentimes means less yield.  Ditto with overextending your lights.  There would be a lot of advantages to getting your grow space smaller--somewhere around 50 sq ft.  And your plant count less--say 20  or so plants, depending on what strains you are growing.  Small indicas maybe more, larger sativas, maybe less.   It must be very time consuming to try to take care of 60 plants properly. 

Your yield has far less to do with plant count and how huge your space is than it does how much light you have, how well you maintain your environment, and how you care for your plants.  Yield is often described as grams per watt (although people usually talk of fractions of grans per watt.  In a well dialed in space with the right genetics and no CO2 enhancement, a yield of 1 gram per watt is good.  CO2 enhancement, if done correctly will bring that number up a fair amount.


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## Mart17 (Jun 30, 2015)

Hey THG!

I have a big room but im not using the whole space for flowering...Im using the 2 corners of the room some sort...ive made enough space from the walls

Ive made 2x 30 plant lines wich is like 5 foot x 13 foot each. So basically thats my dimension more or less a little..

I left a space between the 2 line of plants and i have planty of room inside for other things i menage.
My walls covered with diamond reflector thingy. and the 2 line of plants are almost near the wall....the middle of the room is not lighted at all just the 2 side where the plants are.

Do you think 5f x 13foot is way too underlit for 2x 600w hps ?! 

I have cut my plants from down to top ...lollypop style 

The thing is that i dont want to loose yield...if i cut back my plants number maybe i wont produce as much as now. Thats my worries

Im seriously considering to slowly change my 4x600w hps for 12x 400w marsII led...
In that way i maybe double my light intensity right?!

SO i have 2 line of plants and each line contains 30 plants in a nearly 50 sq ft area. 
Is that way too big?! 
How many plants should i grow under a 600w hps with adjust a wings?!

Yes if im not changing to led i will probably try the air hood method again you are right.


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## Mart17 (Jun 30, 2015)

Another quick question about air cooled hoods...for a 600w hps you recommend the 125 or the 150mm one?! the bigger is the better right?!


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## Mart17 (Jul 1, 2015)

Okay THG i was stupid!
I did a miss calculation about my lighted areas.
Im converted badly im sorry...

My area wich contains 30 plants and 2x 600w hps is 7,9ft x 4,6ft.

Its about 36 sq ft for 2 600w hps.

I assume this is much better )

I decided to go with air cooled hoods till i buy my led lights. I could buy those but first i wanna try out this and elso leds are kinda expensive. I will slowly buy them piece by piece.

Ive read that the lux output is a little lesser with air cooled hoods or cool tubes. 

Can you guys tell me how much?!

Also would be really happy if you guys can help me about 2 items:

http://www.bushdoctor.at/hu/4564/reflektor-spudnik-150?c=1712

http://www.bushdoctor.at/hu/4062/reflektor-coolwing-medium?c=1712

Wich one would be better?!


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## Dr. Green Fang (Jul 1, 2015)

> Ive read that the lux output is a little lesser with air cooled hoods or cool tubes.



It's roughly 5% loss.


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## The Hemp Goddess (Jul 1, 2015)

The loss in lux, IMO, is not as important as being able to keep your temps in line.  

While 36 sq ft is better, it is still pushing your lights to the absolute max.  Do you have any pics of your grow?  This helps us a lot. 

I prefer large hoods if you have the room.  So, I pick the hood in the first link you posted.  I also find that I have a better time keeping things cool if I connect my hoods in parallel rather than in series.  Do you have an exhaust fan?  Something like this?  [ame]http://www.amazon.com/Active-Air-720-Inline-8-Inch/dp/B002JQ4K1I/ref=sr_1_3?ie=UTF8&qid=1435755319&sr=8-3&keywords=8%22+exhaust+fan[/ame]


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## Mart17 (Jul 2, 2015)

Thank you for the advice...ill pick the first one

I have 2 Can fan: http://www.bushdoctor.at/hu/4461/can-fan-rs-150l-/-620m

I want to use those fans for the cooling. I will put those in line.

I pretty much had get in familiar with these air cooled hood and setup. 

I will do it like this: 
http://growconsultantco.com/gardening-equipment-tests/setup-air-cooled-light-reflector-grow-room/

Is there a safe way to send pictures?! If there is a method for 100% safe sending than i will. Here the attach file sending method is safe?!

I cutted my plants yesterday so for the pictures i have to wait till i restart my garden.

I also would like a little help about the cooling. 

I will transer the air for cooling from another room wich has kinda cool temperature. OFC when outside the temp reach 90-95 f that room is still reaches 75-78 but most of the time the ligt is on from 00:00 am -12:00pm. so it means there is a lot cooler outside becouse of the night.

In this case how much does the temp will drop at the flowering room?! Im not using and heat shield and nothing...just my adjust a wings with the light .

Just as i told i will use 1 can fan for 2 fixtures and im having 4 fixtures. 
That 620m3 fan should do the trick of the cooling right?! For 2 hoods?! The duct will be as straight as possible for maximum cooling.

An other question if you wont mind...

In 1 line i will have those cooled hoodes with the 600w hps.

What do you people think about the number of plants should i put under them.?!

Im growing like 5 years now but im only grow this bigger scale in like 1.5 or 2 years. I need to learn how to control a bigger garden like this in summers and also in winters and menage to reach the highest possible yield.

At winter im having a much better time but in summers ive loose too many weight.

Ive reached 70-71 oz several times. I want to reach it as many times possible. Or maybe a little more would be really good 

IM growing white russian from serious seeds. Heavy yielder sativa/indica hybrid. usually i start flower when they reach 19.5 inch


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## Maya_the_englishmastiff (Sep 6, 2015)

Gavita


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## Sweetmansticky (Sep 7, 2015)

What about a plastic tube you could fill with dry ice every few days at the highest point in the grow? Dunno if it would work ppm wise but it sure would be cold!!


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