Can you learn from someone elses mistakes? It's going to sound like I am being a dick, but I'm not. I've made all of the mistakes and spent all of the money on things I'll never use again. I 'd like to see you succeed so I'll tel you what I think. Take it or leave it.
The main issue is that Height will likely be a limiting factor for you. I ran into this very same problem and I think a lot of growers do too in the beginning. 5 gallon pot, plus a 2-3 foot plant = 4 ft not including room for lights and ventilation.
Heat will also be a problem. Small space + low height = big heat. There is no where for it to go. You are make a Betty Crocker Easy Bake Oven. A few computer fans won't cool very much light. CFL's are way hotter than people imagine.
My suggestion is to make a similar box, but make it 6ft tall.. This will allow the heat to rise before it is extracted and it will allow plenty of room for exhaust, carbon filter, lights, hood or reflector and clearance between plant and lights.
This box however would make an excellent veg chamber for future use so hold onto it.
Her is my first setup (Below). After a few weeksof veg I knew I had miscalculated and then built a much larger tent. This box below is 2 x 1 x 3ft tall. Those are 3 gallon pots. See how I couldn't possibly fit even this small 5 week old autoflower in there (below)? It just doesn't work out.
Also as Dad said. You need odor control. You will need a 4 inch vortex fan and carbon filter and fan speed controller.. I really don't see any way around it unless you live in the woods and really enjoy the smell of weed. Weed really smells and it's stressful when your house starts to smell like a pack of angry skunks just moved in.
Small autoflower
Here is my suggestion for a 1 plant first time grow. This setup will allow you to grow quality bud for years even if you never upgrade.
- Northern Lights x Big Bud Autoflower (Since it's your first grow I suggest this strain. It is really easy to grow. Plant it and forget about it. In 8 weeks harvest your bud and have a party.) The problem with bag seed is you don't know the characteristics. It may be seed from a 15 ft monster strain that is difficult to grow or is too sativa or indica for your liking etc..
- 3-5 gallon pot. Any pot will do as long as it has proper drainage.
- Any quality nutrients. Fox Farms, Advanced Nutes etc.. ( All you need is the bloom nutes. Nothing else is required. Veg nutes are not necessary for an auto in quality soil. It will be flowering in 3 weeks)
- Fox Farms Ocean Forest Soil or any other recommended soil for MJ.
- 2x2x6 ft cab
- 4 inch hole in bottom of cab for air intake.
- 150 w Sun Systems HPS all in one lamp. (You can get these for less than you can build some crazy cfl setup for)
- Timer
- 4 inch vortex fan and carbon filter. A fan Speed controller is nice to have to cut down on fan noise.
- Filtered tap water or rain water if you can get it.
- 18 hours of light. Six dark.
You do not need any special elixirs that promise to grow bigger buds. You do not really need a ph pen since the soil should buffer the PH and your nutes will likely lower your water PH to a decent range.. You do not a MH or CFL or fluorecent lights for veg, The HPS is fine.
A small microscope is required so you can see your trichomes. Keep an eye out for bugs.
I hope this helps and saves you some buccos and lost time. Best of luck. Please keep us posted.