Hi Rock420...
Welcome to MP! Where's EVERYBODY at? This thread's like a ghost town...
Let's
liven things up a bit around here...
:lama: :yay: :yay: :banana: :yay: :yay: :lama:
MUCH better... Nothing livens things up by 4 gyrating happy faces, two bananas riding lime green Llamas and a Dancing Banana too!
I've got a similar grow situation going on. I have two closets right next to each other... I use the 2 x 4 x 8 closet for my bloom space and the 2 x 3 x 8 closet for veg growth. In the bloom closet I have a 1K switchable ballast for my main light and a 6 bulb, 4 ft. T5 fluoro for side fill lighting. The 1K is in a 6" 'cool tube' style reflector and I pull air first through a carbon filter hung high in my closet and then through the cool tube. I have a Eclipse 6" 630cfm fan hung on rubber straps in the attic that pulls air out of my closet via 6" duct that goes through a hole in my ceiling and comes from the cool tube. In my veg space I use a 2 ft., 8 bulb T5 fluorescent fixture. I have a 4" intake and depending on what time of year it is I'll keep it passive when it's cool outside or use an inline fan to blast cool air from an a/c unit in the bedroom... often used in 'fan only' mode when it's not hot... IME you're going to need some type of air cooled hood or cool tube to keep temps decent with HID lighting in that tight of a space. Your proposed space really sounds limiting to me if you divide it up too... The tighter the space with HID lighting, the more gusto you're going to need with ventilation.... If you put a 400w MH and a 400w HPS it's going to take a lot of fan power to pull the heat off of both of those lights.
Your 400w lights won't be near the challenge my 1K is to keep things cool and your 8" ventilation is a great choice... VERY efficient compared to 6" or especially 4" ventilation... But I don't know if your fan will be able to pull enough heat off of your setup if you Y the connection and have only the 325cfm inline fan... You could hook things up somewhat temporary and see how it performs that way but I'd hate to see you go through all the construction of separating the spaces only to realize that it's too much heat for the ventilation and design to deal with... If you put a 400w MH for veg and the 400w HPS in your flowering area in the same 3 x 4 x 6 space it's going to be a HUGE challenge the temps within range.... ideally the mid 70's... imho you'd do much better to use the closet for blooming and fashion another separate area somehow for veg. To create separate rooms I've used 1 x 1's and 4' x 8' sheets of insulation styrofoam and then put heavy Panda Film over the exterior to block out light and create a reflective surface on the interior... I've also used 1" PVC for a frame with Panda Film too... OR nowdays there are lots of pretty decent grow tents on the market that would work well for a veg space. The advantage of a DIY construction is being able to make is any size you'd like... but a tent comes ready to set up and go...
I think if you use the closet for bloom with the 400w hps your exhaust fan and intake would work well. You could probably have a passive intake into the closet and your exhaust fan would pull enough cool air from bedroom into the closet to keep things cool... For every square foot of air that's exhausted from your closet air has to rush in to replace it whether it's through cracks around and under the door or through a passive intake hole. As long as you can keep temps in the bedroom in the upper 60's to lower 70's your exhaust fan(s) would pull enough heat off the lights and cool air into your grow and bloom space... So I'm not saying it can't be done but there may be an better solution than trying to do all your growing in the same closet... What I wouldn't give for just another foot of depth in my bloom closet... lol... Also... have you thought about odor control? A carbon filter is the best way to go if you want the most stealth grow room. Your ventilation will help a lot by keeping the air exchange moving to prevent an odor buildup and if you can route the exhaust so it comes out a vent high on your rooftop you may be good to go... Good exhaust also keeps a 'negative air flow' going toward your grow closet and odors can't escape when the airflow is constantly getting pulled out of your closet... And even without a filter, with good exhaust most odors are kept to a minimum. Since the exiting exhaust air will be warm it will rise when it gets outside and there won't be a heavy odor buildup if you keep the ventilation going. I think it's best to keep the ventilation going constant rather than in timed cycles. You can buy a "Speedster Motor Speed Controller" for about $29 online or at an indoor gardening/hydro store and hook it up to your exhaust fan to vary the speed and power of your fan... This gives you lots of precise control with temps... Lots of air movement is required in the summer months but from fall til spring less air movement is required to keep temps in the 70s...
Also... Depending on your climate, running your lights at night could help you maintain better temps too... I run my bloom lights 8pm-8am mainly to deal with summer heat but also helps keep my grow space warmer during lights off which is during the daytime outside. Oh!.... I have a really nice AK48 pheno going right now! It's in the 4th week of 12/12 and it's looking very dense and dank... I grew the strain about 7 years ago and forgot about the extra seeds til I found them this summer in a storage space. Only ONE seed popped of 8 old various seeds and it was the AK48... and it turned out female... YAY! So onward and dankward... It's a very easy strain to grow... I'm doing a test grow in small pots of many strains right now in small 2 gal pots but I usually use 7 or 10 gal containers and do long veg periods...
I've been using Subby's Supersoil mix for a few months and I'm THRILLED with the results. I only had one grow in 10 gal containers with supersoil... a White Widow and a Poison Afghan... The PA turned out to be the dankest bud I've ever grown... I got around 5.7 oz and I know I'll get more next time now that I know the strain better... The WW yielded almost a half an elbow of KILL bud... I had a small WW outside... a clone of the same pheno and it was in a shady spot but it didn't do nearly as well as the indoor WW... The one drag is the WW indoors went hermie at around 12 weeks while the outdoor one NEVER hermied and I pulled it at 14 weeks.... I had some major heat problems a couple of times due to a bad digital timer and I think that was enuf to stress the WW into going herm.... Anyhooo.... The supersoil performed amazingly well... I gave them nothing but water and occasional molasses or Botanicare Sweet for carbos to keep the beneficial beasties happy and some Liquid Karma for humic and fulvic acid... Make sure your read up on the Subcool Supersoil threads... The most important thing is to let your soil sit and 'cook' for at least 4-6 weeks to break down the organics and stabilize the ph... But once you do that you're set for months.... I've got a 44gal Brute trash can outside FULL of supersoil to get me through til spring or so....
So... I urge you to rethink things a bit before heading to Home Depot... There are many ways to get things done and since you have a bedroom available you may want to re consider how you design things to make it easier to control the environment and give you the room you'll need to keep mother plant(s), clone, veg... and BLOOM!
Have a good one...
