70 watt or 150 watt?

I vote you go with the 70w seen as your space is only 1 foot square. Its nice to aim for 50w per square foot but even with the 70w hps your gna be at 70w psf and need good ventilation.

Go with the 150 if you want though better hope you are a ventilation genius though

 

EcoGrow

 

Ok, you are doing almost the exact same grow setup as I am. I have the 150 watt hps, though at first I was going to get the 70 watt too, but I figured they were so close in price, why not double my wattage when the electrical cost at this point is very very low. Ventilation, however, is definately something to think about with this light as it is just a magnetic ballast and thusly, does heat up more than say an electronic ballast.
Anywho, I built mine in a 1.5 by 2.25 by 3 ft space. A 1 x 1 x 4 sounds extreme and it sounds like you will be able to fit two seedlings/small plants and one full grown plant in there. While the 150 watt will definately get you more vigorous growth rates, it probably does heat up more than the 70 watt.

The end answer, however, is that you WILL have to ventilate your light, 70 watt or 150 watt, and thusly should invest that 40 bucks into a small computer fan etc.
The reflector that it comes with SUCKS and does not reflect light nearly as well as a professional grow op reflector. I didn't get a new reflector for it, but after my first yield, I'll just clone a couple under a 60 watt fluoro floodlight in a tupperware container while I up the efficiency of both my light and my box.
HERE is how you make a good reflector for a low wattage hps:

http://68.103.98.234:6667/ogi/modules/growfaq/1440.htm

MrE (the designer and creator of abovesaid reflector) was the man in the old OG imo, he made a 1 x 1 x 1.5 ft file cabinet that looked like a standard file cabinet that actually grew a few clones under a 70 watt to flower using scrog. He usually got a couple ozs from one or two tiny plants, but he made sure to have a seperate, slightly larger, cloning chamber in a tupperware container etc. After OG went down, I did what I could to find out as much on his method and found a couple cached links, let me see if I can't dig those out of my favorites folder . . .
. . . well, it seems they aren't loading very quickly, but here it is:

http://72.14.203.104/search?q=cache:yyQa-vfYe34J:www.overgrow.com/edge/showthread.php%3Fs%3D%26threadid%3D163849+MrE70wCab&hl=en&gl=us&ct=clnk&cd=2

the pics aren't there anymore, but you can get a general idea of how it worked from his description, etc.

Best microscrogger that I had ever found and it was all DIY setup. Really sweet.
Anyway, another thing you asked about was a screen with some activated carbon for odour control. Yep, MrE did this, it's called a "carbon scrubber." Here's what you do. Get two of those blue screen things from your local hardware store, get some actived carbon from your local aquarium/pet store (it's used for aquariums in some form or fashion). Get something that will evenly disperse the activated carbon throughout the filter, like a plastic grid of any kind, if you can't find one it's no big deal, but it will make it more efficient. Pour the activated carbon carefully and evenly into one of the blue screens and put another one on top of it. Sandwich the activated carbon inbetween two of the blue screens and glue it, staple it, SOMETHING to keep them together. Then put it on the back of your box.
I have yet to actually test the carbon scrubber, but that's my plan for my own gro, so I hope it works. If not, get these, unoit was telling me they work pretty well:

https://justn-tyme.com/store/product_info.php?cPath=51_30&products_id=256&osCsid=a132f26d0af2a0360b62af372c6ee001

If you can't get a good reflector or simply don't have the funds to build one (like me). Use the one on they send to you and modify it for better ventilation using info from here:

http://68.103.98.234:6667/ogi/modules/growfaq/1151.htm

I simply attached a small 9mm computer fan to the reflector by drilling holes in it to push the air out through and screwing the fan inside it (it fits, but just barely, and you must never turn it off as if the light heats up too much, it could possibly melt the plastic computer fan). You must learn how rewire electronics safely and in an organized fashion. You can learn all about that here:

http://68.103.98.234:6667/ogi/modules/growfaq/1655.htm

You must remove the ballast from the reflector as together they heat up ALOT. Get a computer power supply box or some sort of box with a hole fitting for a 10 mm computer fan on it. Put it in there and make sure it is secured somewhat inside the box, but not packed tightly. Keep a fan on the ballast and the fan and you will not have to worry about it heating up much, mine heats up only about 2 degrees above ambient air temperatures.

Remember when you finally get your light (whatever choice you make) to orient it perpendicular to your width, though in a 1x1 it probably doesn't make a difference, so maybe forget about that, but if you ever have a space that has different width/depth dimensions, keep that in mind.

Hope this helps, good luck.

 

in a 70 watt microscrogging setup, I've heard you can yield up to a couple ozs per harvest, but for the first one even mrE only got a quarter oz his first time (did much better later on though).

Taking the ballast out isn't that tricky with those lights since they pretty much designed them to be taken apart. Take off the light shield and carefully unscrew the bulb (use a paper towel or some sort of clean sheet to cover your hands as the oils from your hands can cloud the bulb, if those oils heat up it can severely reduce the quality of your bulb) The reflective aluminum inside the hood is easily removed, but you'll need a screwdriver.

Remove the mogul (the part that the bulb screws into) using a screwdriver and by this point you should be able to remove the reflective aluminum entirely. Inside you will see wired to the mogul the magnetic ballast. It's basically a big magnet with some wires coming out of it. This thing heats up quite a bit and the fact that it is simply put together with the light is a flaw in nearly every security light's design.

Now the tricky part is rewiring the ballast so that it is extended far away from the light, so you'll need to research the size/gauge wires you'll need and you'll have to get some heat shrink tubing and a saudering iron and some sauder to make electronically safe connections. These things are cheap individually, but put together can run anywhere from 20 to 40 dollars depending on your area, but any good electronics store in your area will probably have these things for relatively cheap. Once you have rewired (takes a while) put the magnetic ballast in its own metal box with a computer fan attached to it (wire the fan to a 9v or 12 v transformer (transformers are cell phone chargers basically, but you have to convert volts to amps to determine which one to use on the fan, just takes some basic mathematic conversions)). Once you have attached a computer fan to both the light hood and the ballast box, it pretty much won't heat up more than 2 to 4 degrees ambient air temperature.

Hope this helps, wiring and electronics was the hard part for me and I simply had to have someone else do it for me the first time and I would probably still need help were I to repeat the process. But if you do enough research, relax, and TAKE YOUR TIME, you should be okay. Good luck.