2x400w HPS in Dr-90 growtent?

Hello guys, i have a Secret Jardin Dr-90 growtent(3x3x6) and currently there is a 400w HPS with cooltube in it. I use an RVK 125mm FAN to cool it and it seems to do a descent job. Temps are between 67-72F(right now the temp is at 68F). If i bought another 400w HPS with cooltube, would it be doable to have both HPS with cooltubes and cool them with a 150mm RVK fan without temps going insanely high(efficiency 800m3/h)? Thanks for any answers guys.

Run em vertically, I don't see why not.

Thanks for answering me my friend, vertically would be hell lots of fun but i am afraid i can't. I am thinking about putting my current cooltube next to the one i am planning to buy in the distant future and cool them both with a bigger fan. I was told that 800w HPS even with cooltubes would be hot in a space like that (3x3x6 as i said), but with my current temps at ~68F, its very difficult for me to imagine that temps could go above 80F

I think you ought to buy a bigger tent. 800w for a 3x3 space is overkill.

Could you please tell me why you believe it is overkill? It would be too much in terms of heat or in terms of light intensity?

I've got 800w in a 4x4 tent, open air reflectors, and I'm only at 81F.

I'm going based on your lumen footprint. It's not overkill as far as heat or anything. I just don't think spending the extra money for a 400w setup is really going to make a difference. The 400w you have is more than enough to cover that space. If anything maybe just hang a few CFL's.

I could add 2000w to a 4x4 tent and still keep it at 73 degrees. It has nothing to do with your temperature and everything to do with wasting money and electricity. Why bother.

Sorry phillip. I'll go take down one of my lights. I didn't know one 400 was just as good as two.

Never said you had to take down your lights man. Calm down! Seems like you are a little sensitive. You do what works for you. I'm just giving my opinion to Paparov. This is his thread and he asked a question. Plus, pay attention, you have a 4x4 tent and he has a 3x3 tent. There's a difference there. And I never said one was just as good as two but common sense should tell you that you don't need 800w in a 3x3 space. Grow up cry baby!

Now phillip, that hurt.

phillipchristian said:

I'm going based on your lumen footprint. It's not overkill as far as heat or anything. I just don't think spending the extra money for a 400w setup is really going to make a difference. The 400w you have is more than enough to cover that space. If anything maybe just hang a few CFL's.

I could add 2000w to a 4x4 tent and still keep it at 73 degrees. It has nothing to do with your temperature and everything to do with wasting money and electricity. Why bother.

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Well, based on the lumen footprint my current HPS has about 55.000 lumens( i have used it for 6 month in the past, so it could emit less than that) if i place it at about 1ft away from the canopy of my babes. If i added another 400w HPS, the optimal lumen footprint would be about 100-110.000. Dividing it by 9 square feet gives ~11.000-12.000 lumens for each of the 4 plants i have in the growtent. Don't get me wrong, i am on a pretty tight budget and i would not spent 320$ just for the fun of it(that's the money required for 400w hps bulb, ballast, cooltube, and a bigger inline fan) over a period of 2 weeks+electricity cost. Cfls would have to be pretty close and my space is going to be limited, so limited, that i could not even add them as side lighting. The only way to add extra light would be if i added it above tha plants. At the beginning i thought about adding a 250w HPS with cooltube, but it would have to be lower than my 400w HPS to have the maximum lumen footprint(~29,000 lumens). The cost for the 250w is only 15$ lower than the 400w HPS and the difference between them is vast. I even thought about leds, but they are so f$cking expensive and i haven't found them anywhere close to me. I am looking for ways to be as efficient as possible in the restricted place i have for growing, i know that there are many factors that contribute to a good harvest and lighting is one of the primary factors. It's only my second grow, pretty much i am a noob, so it is logical to assume that i would get about 0.5g/watt, if not less. So, wherever i have the option to upgrade my equipment, i am willing to do it in logical margins. Cfls+leds are not an option, so that leaves me with HPS.

Right now with just 1 400w you are at around 6000 lumens & 45 watts per square foot and those numbers are just fine. If you wanna beef it up then go for it but in my opinion you don't need to. If you want to or feel like you need to then only you can decide.

phillipchristian said:

Right now with just 1 400w you are at around 6000 lumens & 45 watts per square foot and those numbers are just fine. If you wanna beef it up then go for it but in my opinion you don't need to. If you want to or feel like you need to then only you can decide.

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Well put. Everyones grow is different and only the individual person can decide what is best for their situation. Thats what makes all of us unique. +rep

Well, after thinking a lot about it, and taking some more opinions i decided to add my 250w cfl(its got blue spectrum, but i am going to keep it for the rest of my grow) in the side of my tent. I know that now it would be possible to add another 400w in terms of temperature but in about 1-2 months for now, i am sure things could get out of control withou an a/c. Instead of buying another 400w HPS, i am going to buy a 250w HPS for my smaller tent (Homebox XS), i believe this should be fine.

Good Luck! Happy Growing!