Confused About Ventilation

As the title says I am confused. Let me lay-out the ventilation set up I have planned in my grow room. I have a 6" cooltube reflector with a 600 watt HPS bulb. I also have an EcoPlus 465 CFM Blower. My thoughts are to hook one end of the blower to ducting connected to one side of my cooltube. The other side of the blower is connected to ducting that runs up through a hole in the ceiling of my grow room. At the other side of my room I plan to put a 9" pass intake hole positioned in front of my AC unit so that the new fresh air is cooled then blown in the direction of my plants. The open end of the cooltube will draw in the cooler air and pass over the bulb and out through the blower and into the attic right?

My confusion arises when I look at pics of every cooltube out there and see they have ducting on both openings on both sides. I understand that this cools the bulb, but how does it help to bring in fresh air? If i am adding co2 will I even need to bring in fresh air or just remove the heat and circulate the air in the room with the AC? I included a rough drawing to show what I had in mind.

My room is 5'X10'X11'.....I did the math (550CF/3=183 183X1.6(ducting)= 294 294X1.6(600W Light)= 469 CFM) So according to the ventilation math a 465CFM should be enough to exchange the air in a room my size in 3 minutes, with the light and ducting included.

the idea for the cooltubes are air comes from an outside source through the cooltube and out of the grow area. the air pulled from the room would not be as cool and you would be putting unscrubbed air into the attic.

I am going to speak from experience, SWIM has a cooltube with a 1000watt hps in it -- matched with dual 400s with MH in them... the cool tube leaves hot spots when you do not have MOVING AIR going to and from it. The way SWIM has it setup is SWIM has a 465cfm fan boosting air to it and a 100cfm inline fan boosting air out of it, the outlet is connected to SWIM's exhaust setup (another 465cfm fan). In total SWIM has six fans...three 465s intake, three 465 exhaust. Originally had 265s... SWIM likes the 465s as there is no odour and the exchange allows constant fresh air.. SWIM can also cut off the exhaust/intake setup to use CO2 when wanted. Works beautifully. SWIM's room is somewhat small.. 12x12x10 but SWIM has it A/C'd and Balanced.

The reason multiple fans was used is so that there is no daisy chaining/running inline of the lights/ducting. Each corner of the room that does not have the a/c (fourth corner) has its own intake/exhaust setup.. and the one cooltube shares its setup with one of the ducting setups.. confusing but efficiency wise it works.. you will be fine with the setup you are going to be using. The air would be cooler/cool the light more if you could setup a direct ducting from a/c to the cooltube then from the cooltube exhausted.. you could use the setup you are talking about where the a./c is cooling the room so the air is going to be cool already and have it drawn in and over the bulb on the open end of the cool tube.. but efficiency wise if you setup a straight off cooling setup to the cooltube you will have a cooler over all temperature in the room.

SWIM's tried both ways and would rather give each light its own intake/exhaust cooling setup and all is well.. share the cooling and its efficiency drops.. what size a/c unit are you using?

i run a 9500 BTU in a room that is less than 60sq. ft. The passive intake will be in front of the AC and will be blown towards the cooltube by cool air coming out of the AC which is about 5-6 ft. away from it. Temperature in the room and odor control are the least of my concerns.....the AC keeps the room around 85-88 at the canopy level directly under the light and the air going to the attic doesnt need to be scrubbed since its in a garage that is secured and off limits. The main reasons I am hooking up this exhaust is to bring humidity down from the upper 60's low 70's and to bring in fresh co2 enriched air from outside my sealed room. Also if i can cool the reflector even a few degrees by exhausting out the hot air then i can lower the light closer to the plants.

As for multiple fans, i am trying to accomplish my goals of humidity, temperature, co2, and air cicrulation control as simply and cheaply as i can effectively do it. I was hoping this cheap, high CFM fan with a few feet of ducting connected to the cooltube and a passive intake positioned in front of AC would do the trick. Also i have read you can use co2 tanks w/exhaust if you run them on seperate timed cycles....15 min exhaust/45 min co2 dispersement is what i was thinking. I just want to make sure this setup will be effecient and wont hurt my fan or cootube. If anyone sees any flaws or has any suggestions i would be eternally grateful kiss-ass

Err... a bit high for an indoor grow.. been doing this 15 years and never had an indoor grow go above 78 degrees Under normal conditions the ideal temperature range for indoor growth is 72 to 76 degrees.. at night the temp can drop 0-15 degrees the temp should not drop more than 15 degrees at night. Daytime temps above 85 degrees will slow/stop growth.

Veg plants go best when relative humidity is between 60 to 70 %, while flowering is best between 40 and 60... higher humidity effects transpiration.... slow transpiration = slow growth.

Are you carbon scrubbing? Do you have a filter? I also use the same method but I have everything on a controller. If you're using co2 youre temps go as high as 95 for some strains.