Are these solid plans for 2 400w tents?

What's up rollitup? I have been working hard on plans for my new grow set up and I want to run it by the community before I go bust open my wallet.I have a small extra room in my home and I decided it's time I start taking full advantage of it. I want to build a veg tent with flouro tubes and two flowering tents each with it's own 400W HPS. The flowering tents will be 3'x3' and will be 4' tall. I plan on using an air cooled reflector and setting it on top of the roof of the tent rather than hanging it inside the tent. I want to remove the glass from the reflector and vent the tent through the light. Each light will have a short run of 6" ducting that will lead to a box containing a carbon filter and 6" 435cfm fan. The fan will blow through another short piece of 6" duct and out the window. Each tent will have an 8" intake with a 300cfm duct fan and two 90* elbows to act as a light trap. The veg tent will also be in this room, and will be 4'6"x2' and will be 3' tall. There will be 3 - 4' 2 bulb 32W T8 shop lights hung close together for lighting. I am putting a 6" exhaust out of the top corner with a 160cfm duct fan on it. This air will simply be exhausted into the room. There will be an 8" passive intake with a 90* elbow to reduce light leakage. All tents will be built with 2"x2" pine and wrapped in 6.7mm thick mylar.

I hope these plans make sense to anyone who tries to read them. I am pretty confident in these plans but wanted some opinoins on a few aspects. For the light trap on the flowering intakes, will 2 elbows do the trick? Or should I use 8" ducting and wrap it in a loop instead? Also, I am exhausting the veg tent into the room as I don't expect it to generate much heat and I want the larger fan to focus it's power on the flowering tents. Is this okay or should I hook this exhaust up to the same box as the flowering tents. My most important question however, regards the 400W reflector. I know a mid-sized reflector will cast the appropriate light footprint for my small tent, but will a larger reflector be a better suit to my plans on exhausting all the air in the tent through the reflector. Here are the two reflectors I am looking at getting right now. Thanks to anyone who takes the time to read this and help me out.

http://htgsupply.com/Product-EasyCool-6-Reflector.asp
http://htgsupply.com/Product-Big-Kahuna-Reflector.asp

Here's a rough sketch of the flowering tents I did on paint.

Ok let's start slowly.

That was quite alot to read.

Lets start with the 2x400w in 2 seperate tents.

Why 2 seperate areas?

IMO you would be better served to create a slightly larger single space to put both 400w.

Have you contemplating any room for you to get in the tents to work? Watering? Pruning/training? Have you considered a drainage system of sorts? Its a royal pain in the ass trying to play Tetris with plants come watering time.


As for the reflectors. The big kahuna is a reflector for 600w-1000w hps systems. Your 400w would be lost in a reflector that size.

I would be a little concerned with whether both tents would exhaust the same but if you switch to a single room for flowering that should help eleviate any issues.


I'm not too sure how the filter and fan in the box will work as you are asking that fan and filter to pull from the tent to the box. Have a backup plan for ventilation. You may need to add the filter into the grow room. To do this you would need more height in your tents.

Is there a height restriction?

I would want more height as it gives you some fail safe incase of high temps.


J

Thank you for such a thorough reply. The reason I am using two separate tents is that the circuit can't handle running both lights at once as there are other functioning rooms in the house on the same circuit (<--that's the guy that built this place) I will run one tent from noon to midnight, and the other tent from midnight to noon. I'll stagger my grows and should be able to harvest damn near every month. I have enough space in the room to pull the plants out to water and set them back in after, which is how I do it now in the closet. It takes a minute but it gives me a good chance to look at my plants closely and under natural light. I do mostly organics so a simple catch tray under my pots has suited me fine. And as for the tents exhausting the same, they aren't positioned the way they are in that paint sketch. The room is only 8'6" across and each tent is in the corner with the fan/filter box in between them. The lengths of ducting from each tent to the box will be the same, as will be the shape of the path. The reason I have the fan filter in the box like that is I couldn't figure out another way to vent two separate areas with one filter. One end of the filter is capped. The ceiling in the room is about 7' so I have more vertical space, but because the light is in a fixed position I didn't want to set it up too high. I'm glad to hear the big kahuna is overkill for the 400w, as the other reflector is cheaper and ships for 60 dollars less! Do you think those intake fans are too strong in comparison to the exhaust fan? Thank you again for reading my overwhelmingly long posts, but I am excited to finally get my grow upgraded.

Be prepared to redesign your ventilation, that's all I was saying.


As for intakes vs exhaust.

If your exhaust is 435cfm then anything with around 10% difference is fine.

So 435cfm exhaust use a max of 390cfm intake. This way negative pressure will always be around keeping smell leaks from being a problem.

Elbows should be fine for light traps too.



J

Thanks again man. Any ideas for a better ventilation design. What if I build a box around my window and set the filter in the box and blow the fan into the filter. Here's a rough idea of what I mean. The location of the tents is more accurately shown here, although the fit is much tighter.