4'x4'x80" Tent: 600 or 1000 watt HPS?

I’ve been planning my first indoor grow for about 70 years, it seems. I’ve been delayed several times, but I’m finally gathering equipment and am in striking distance of getting started.

Here’s what I’ve decided on so far:

I have a 4x4 tent, 80 inches tall. So I’ll use it.

I’m gonna do DWC. Debating on RDWC, but may save that for second grow. Keep it simple to start, right?

I fondly remember Northern Lights from back when I was cool. So I wanna grow them. I figure four in my tent, scrogged.

I’m gonna go all out and get a really good air pump (or 2) with a soda can airstone in each of the four buckets. For buckets, I am leaning toward 10-gallon tubs.

About the light… I have looked into LEDs, and they look great, but I just want to go with HID to start. Maybe I’ll try LED later.

I had decided on 600 watt to begin with. But I figure 1000 can’t hurt. As far as heat goes, I think I might possibly have that covered. Maybe. See, my tent has to go in my basement, which is not climate controlled at all. I don’t want to lose my first grow to temps or humidity after being delayed so long, so here’s my plan. I’m gonna run an intake duct from an upstairs room down through the floor into my tent. The exhaust will go up through the floor into another room. Carbon scrubber and all, yes. The ducts will run up between walls and suck in/blow out through floor grates that I’ll install. It may take a bit of dickering to work the carbon filter in, but that stuff if kind of fun for me. Total geek.

Anyways, 1000 watts in a 4x4? What do you think?

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Oh, I’m not just looking for advice on the 600 vs 1000 watt dilemma.

I’d welcome feedback, advice and criticism on it all.

I reread my post, and in the beginning I said “Keep it simple in the beginning, right?” Then I get into running intake and exhaust ducts through the ceiling/floor, lol. I’m sure someone else has done something like that before though. Heat/humidity can be a real pain. Tapping into climate controlled living space just seems perfect as a solution.

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If heat maybe an issue HPS light is going to compound that. Any particular reason you don’t want to go with LED’s? Here is a DIY LED that may interest you. Just a thought anywho good luck with whatever you decide!


What about 2 400w CMH bulbs?
Im guessing the coverage is better with 2 smaller lights than with one single powerful one…

Im using LEDs because im in tropical weather and managing heat with bulbs would be more expensive for me…
Also do not like the idea of having something that can break and fill my tent with glass…
Leds are also expected to last MUCH longer than a bulb…

Anyway, i have the same size tent, and if it were me, i would go for 2 smaller bulbs than 1 big one, just to spread the lights a bit better…
Also, if you have 2 smaller lights, you can use just one for the first weeks when the plants don’t need full power and then add the second one later.


i think 1000watt is too much for this little space, you will most probably get problems. I would go for 600-800watts max, probably more like 500. But then again it depends on the light. I work with COB’s & LED’s so I don’t really know about hps.

PS maybe you want to check out the Amare SE500 if money is not a problem. I use the 300 in a space a little smaller and it is perfect. I promise.


1000 watts is fine for this space if you want it, but 600 will suffice. I run 1000 watts of HID in a 4x4 tent.
Here are some tips:
Get a digital dimmable ballast. That way, if you get days where it gets to warm, you can drop it down in wattage. You can also use this to be more gentle on your young plants when you have your Metal Halide bulb in.
You need to get an air cooled reflector. This is the key item that keeps an HID light from heating up your canopy.

Not that you have to get the same as I have, but the one I use (from growershouse) consists of:
Quantum Digital Dimmable Ballast 1000W 120/240
XtraSun 64 Air Cooled Reflector - 6 inch
Eye Hortilux Super HPS Enhanced 1000W
Ultra Sun MH – 1000 Watt – 4.2K


1000 watt is working good in my 4x4x70 tent. It can take six 5 gallon buckets. But unless they are slim profile, it gets crowded. Especially if you do LST. Which I recommend to double your bud count.
Of course, exhaust fan is needed. A 6" fan will do.


Oh, I should also say - even if you go with the 600 watt light, still get a digital dimmable ballast. It’s good to be able to dim things down if you need to.


I use a 1000mh/hps in a 3x4x5 tent, but use cooltube so heat is very controlable. Better to have more than u need for light than not enuff rite? I can run it as close as 9-10inches from cooltube glass to tops. Glas is approx 2 1/4 inches from hps bulb and approx 1 1/2 from mh bulb.
I have it in my 5x5x7 flwr room rite now at 8inches from cola tops to cooltube glass


I want to go with HID, at least for my first grow or two, because I’m more comfortable with them. I’ll know what I’m dealing with. LED will be totally a totally new concept for me. But I checked out your link and I love it. When I do try LED, that’s what I’ll do.

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