I am working with:

10" tall x 10" long x 3" wide closet (cover in mylar)
250w HPS
4g DWC w 5" round airstone
12" oscilating fan
Sharper Image Ionic Breeze air filter


I am having some temperature control issues and want to create decent ventilation.


What are the most cost effective method?

I have seen a few set ups...

1. Intake light cooling only:
Intake fan > HPS light > Carbon filter

2. Exaust only:
Exaust fan > filter > attic

3. Seperate intake and exhaust:
Intake fan > room
Exaust fan > filter > attic


Any suggestions for my senario?

Thanks

From my experience, when i grew tomatoes indoors year round, i just placed a piece of glass under the light that covered 80% of the area between the light and plants. It sort of kept all the hot air in the upper 20% of the box. Make intake holes in floor, they suck up through glass "holes", then across your bulb, and out the box. With a 150HPS temps stayed around 71-75 no problem during the summer.

I have found these fans to work wonders in small spaces and limited wattage(silent)--http://www.4hydro.com/growroom/ecoPlusAxialFans.asp--

Anyone else have further input?

I vote for you to do it RIGHT...

Dedicated fan for your aircooled light...

dedicated fan for exhaust, with carbon filter...

Passive or active intake depending on your needs... I have active as I blow cold air from another room...

Here is a drawing by AL B. Fuct that shows the correct way to install ventilation on a small enclosed space...

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