I have a 6.5'x4x4' grow tent. I want to vent it as cheaply and quietly as possible. I don't want to spend too much money so I want to just have one vent/fan and one circulating air fan. Would it provide enough cooling to just have one 6" exhaust vent and fan connected to the top, and have a circulating air fan in the grow tent? This is what I'm thinking of buying: http://www.homedepot.com/p/Honeywell-HT-900-Table-Air-Circulator-Fan-HT-900/202182997 and http://www.homedepot.com/p/Suncourt-Inductor-6-in-In-Line-Duct-Fan-DB206/100067594 and http://www.homedepot.com/p/Unbranded-6-in-x-25-ft-Flexible-Aluminum-Duct-FL0625-4/100252513 Thanks for the help!
Not for the size tent you have. You're going to need a lot more than an in-line, you're going to need a centrifugal. The goal is to replace the air in the tent fast enough to eliminate stagnant heat. A circulating fan won't do it either; it'll just move the warm air around. If you're on a budget don't get one of those honeywells...they are strong but won't be enough for your tent. Get one of those box fans and string/zip tie it up in a corner. That should do just fine.
Would stringing box fan to top negate my 6" duct fan? edit- centrifuge vent way too expensive and loud for my setup. The grow tent is right in my living room lol.
No, it's not going to effect any air being pulled through your light. Getting a centrifugal is going to be pretty much mandatory...especially with the hot seasons coming up soon. I'm assuming you're running a 1000w? If ducted correctly, a high quality fan is MUCH quieter than you may think. Canfans in particular. Look for them on craigslist; trust me, if you look for any decent amount of time, you are going to find one, and at a great price. 2 of my Canfans retail new for 200 each, and I picked up both with only about 6 months use for 80 total. Just ridiculous...
awesome thanks. I found some canfans on craigslist, shot the guy a text. One quick question. I heard it is recommended to replace total air volume once every 5-8 minutes. With my grow tent, it's only around 112 ft^3, so why won't the inline fan I linked be good enough since it's rated for over 200 CFM? Am I thinking wrong?
Well, you have to also factor in areas where you are going to lose efficiency, like in your ducting and when you use a carbon filter. I've seen those inline fans, and trust me, they just don't have the oomph. More is better. It's almost impossible to have too much air movement. You also have to remember that with a strong centrifugal with ducting leading out a window, you are going to create a strong negative pressure in your room, and not just the tent. This is going to equalize your inside temperatures with the temps outside. Goes a long way...
Get a variac controller (link below) for your inline fan. It has been one of my favorite purchases. The adjustment versatility helps to extend the life of my filter too. Cheap inline fans are usually louder than better crafted fans like the vortex for instance. http://www.amazon.com/Variac-Variable-Transformer-300va-Output/dp/B006NGI8VS/ref=sr_1_2?ie=UTF8&qid=1397670187&sr=8-2&keywords=variac