Ventilation, exhaust, fresh air for 600w tent.. I am running 9 fans!!!

I need some serious help with the efficiency of my setup..

I am flowering in a grow tent, 4.5' x 4.5' x 6.5' tall (131cubic feet)

600w hps, digital lumatek ballast is in a nearby closet,
hydrofarm hood (rectangular with a 4" port on each side), aircooled with a 160cfm inline sucking air through the light right outside the tent with a 180cfm squirrel cage 2 feet down the line blasting it out through the window. Both fans pull 72 degree air through a 4" hose from outside the tent, through the light, and push it out the window.

exhausting: for radiant heat at the top of the tent I have a 465cfm squirrel cage exhaust fan mounted in the window sucking through a 4" hose in the front top exhaust port. I also have a 250cfm computer fan that in mounted in the rear exhaust port to move air out of the box and out into the 72F room around the box. These are plugged into a hydrofarm thermostat set to maintain 80F at the canopy (I am adding Co2) The problem is that the fans run constantly instead of every once in awhile, so they suck out my co2...

Intake is a small fan outside the box blowing air in on one side vent and a 105cfm computer fan sucking 72F degree air in in the intake port. All other vents and ports are open for passive intake.

I also had to add a 105cfm computer fan inside the tent, suspended and trained on underside the 600w light to diffuse the heat directly under the lamp. Then there are 2 gentle oscillating fans inside the tent to move the air and co2 around and a heater fan to heat it at night.
All exhaust fans turn off when the light does, but the oscillating fans and 105cfm fresh air intake fan stay on so stale air doesn't sit inside the tent..

Temps at canopy level are 79-81 degrees with room temps at 71 degrees.
I really have to pump the AC into the room to keep the canopy at 80 degrees, Question: is the aircooling cfm or the exhaust cfm more important? I am running 9 fans total in this grow, it is getting ridiculous!

Here are the options I have thought of, But am open to ideas.
A) Replace the 250cfm computer fan exhaust with another 465cfm, upping the radiant heat exhaust to 930cfm
B) Replace the 240cfm of air cooling on the light with 465cfm or more?
C) Or would it help to just switch the 240cfm of air-cooling to exhaust, and then air cool with my 465cfm?

any ideas are appreciated. I even have a carbon filter, but haven't hooked it up because my exhaust has to run constantly as it is.
All vent hoses are short and bends are to a minimum..

Here is a picture of a 16+ gram cola bud that just grew inside,

I would just like to improve the efficiency of the fans.. Any input on exhaust, air-cooling and how to reduce canopy temps is appreciated! thanks!

bump.. anyone?

I will be honest I cant read all that, I am too high. But it cant be that complicates. I will share what I do. I have a 600 lumatek in a 4x4x6 tent.

I run a cooltube. I pull all the air out with an eight inch inline fan. I exhaust it with a charcoal filter at the end right out the window. It works great as long as it shoots that ho air right out. I have also run it with a 6 inch inline fan and it worked ok. In fact I have also in the past run it with the 6 inch and no hood and I just has to keep it an uncool 2 feet from the plants, Emergency style.

I also run house air. I wish I had a portable air cond to put near tent.

I think ozone just rapidly killed all my plants. Be careful but it works. lol.


So I think you need to ditch computer fans and get a real inline fan and exhaust out. That will save on air too.

EBay has real inlines for cheap. I use the valueline model and have no complaints


I use an oscnilating fan to circulate air. Make sure it moves as it will give windburn wicked bad. Lol, I have learned everything the hard way.

good luck.

tea tree said:

I will be honest I cant read all that, I am too high. But it cant be that complicates. I will share what I do. I have a 600 lumatek in a 4x4x6 tent.

I run a cooltube. I pull all the air out with an eight inch inline fan. I exhaust it with a charcoal filter at the end right out the window. It works great as long as it shoots that ho air right out. I have also run it with a 6 inch inline fan and it worked ok. In fact I have also in the past run it with the 6 inch and no hood and I just has to keep it an uncool 2 feet from the plants, Emergency style.

I also run house air. I wish I had a portable air cond to put near tent.

I think ozone just rapidly killed all my plants. Be careful but it works. lol.


So I think you need to ditch computer fans and get a real inline fan and exhaust out. That will save on air too.

EBay has real inlines for cheap. I use the valueline model and have no complaints


I use an oscnilating fan to circulate air. Make sure it moves as it will give windburn wicked bad. Lol, I have learned everything the hard way.

good luck.

Click to expand...

Ya ditch those computer fans, those thing are part of the problem and an oscillating fan will help move the air around

Get a strong intake fan and exhaust, hot air can not stay in there if it is getting sucked out, also put the exhaust fan as high in the tent as you can, this will also help removing the air from above

Hope this help, I am sorry I am not as stoned as the other guys

But I on my way

T

I run 2 fans both 340 CFM. One pushes through both of my sun tubes and the other is hooked up to a temp humidistat with a Co2 lock out. I keep 2 600 watt HPS bulbs cool like that and keep the room at 75 to 80. If you keep your lights on one circuit completely sealed from your grow and get a Co2 lockout you won't lose the Co2 a quickly.

Thanks guys, I like the Co2 lockout idea, I hadn't heard of that.

Though, I must say that if you read the post I am exhausting up high already, with a 465cfm squirrel cage PLUS the 250cfm 6" computer fan in another exhaust port.
(I am just saying that so I don't keep getting that response...)


I THINK THE PROBLEM WAS JUST THE WAY I WAS READING MY TEMPS??

I shaded my temp gauge and It revealed that it was actually 75.9 degrees at the canopy (not 80-81)... So I was able to turn my exhaust controller up a couple degrees and am keeping the air temp at 78-79F This should fix things...
I also removed both intake fans to reduce turbulence, and replaced the 2 oscillating fans inside with 1 large one.
Now I am down to 6 fans, 4 if you consider that the 2 exhaust fans run part time instead of constantly.

Since I heat the tent at night to keep it at 78F, I am not actively intaking or exhausting at night, but the oscillating fan is on inside 24/7 to keep the air moving. Is that ok? Someone mentioned I need to exhaust at night but that will require an additional controller box..??

Thanks!

Had to be something like that. Using your numbers you are changing the air in your 131 sf room 3.5 times a minute? No way you can have a heat problem. Good rule of thumb is you need to exchange the air every 1 to 2 minutes. So 131 sf = a fan of the same size to do it in 1 minute. You also need an equal flow into the room.

peace