4x4 venilation for 400 watt hps and tent

Hello all, I'm a little stumped on this one. Ill be running a 400 watt hps cool tube in a 4x4x6.5 tent. Would it be better to run filter to light tube to fan and exhaust or seperate the light and filter and run an intake line up to the light and use a seperate fan/filter setup. This way I would have to buy 2 inline fans. One for the light and another for the filter. Will the room stay cool enough with it all hooked together?? Seems more efficiant this way. And what size fan or fans should I get. The temp outside the room will stay around 70-75. Thanx all. PS-I can run an intake line from my central AC if I had to. There's a floor vent right next to the tent.

Josh27glock said:

Hello all, I'm a little stumped on this one. Ill be running a 400 watt hps cool tube in a 4x4x6.5 tent. Would it be better to run filter to light tube to fan and exhaust or seperate the light and filter and run an intake line up to the light and use a seperate fan/filter setup. This way I would have to buy 2 inline fans. One for the light and another for the filter. Will the room stay cool enough with it all hooked together?? Seems more efficiant this way. And what size fan or fans should I get. The temp outside the room will stay around 70-75. Thanx all. PS-I can run an intake line from my central AC if I had to. There's a floor vent right next to the tent.

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if you did the light as a seperate setup from your filter, and just wanted to extract the heat out from the bulb (hence why i assume you got the cooltube), you could probably get away with using a duct booster (4'' or 6'' depending on your tent specs, etc). you may need to use two duct boosters but if your simply trying to run air across the bulb and out of the tent, one should be enough. there usually like $30-35 USD.

I have about the same size tent I'm about to purchase real soon. I'm going with a 600watt hps/mh w/ cooltube as well. I'm planning on using two inline fans. One for intake. One for charcoal filter running it through my light and then out. I'm going to get two 6" fans, one high velocity w/controller and one inline ducting fan.

I just posted a thread and I have a little diagram (but it doesn't show the charcoal filter or ducting). LINK

Yea the reason I got the cool tube is I want to be sure there won't be a heat issue. Ill be growing in DWC and I need to be sure I can keep the rez temp down. Also if I decide to upgrade to maybe to 600 or 1000 bulb in the future there won't be an issue with heat from the bulb. If I mounted a filter to the top of the tent and ran ducting to the tube then ran from tube to exit would 450cfm fan be enought to cool the light and make good use of filter. Mount fan inside or ouside of tent?

Just wondering is it better to pull air thru the light or or blow it over the light. Thanks

I have just bought a coolstar reflector for my 400w hps and I use a PC fan blowing through the housing. The reflector is in a grow cab and the air is blown straight through. I ducted it seperately so that it didnt effect my main air extraction and inline fan. The reflector is not airtight so sucking the air out would also pull unfiltered air from the cabinet.

I used the fan to blow the air so that the hot air didnt damage the fan.

Fonzie

Fonzie said:

I have just bought a coolstar reflector for my 400w hps and I use a PC fan blowing through the housing. The reflector is in a grow cab and the air is blown straight through. I ducted it seperately so that it didnt effect my main air extraction and inline fan. The reflector is not airtight so sucking the air out would also pull unfiltered air from the cabinet.

I used the fan to blow the air so that the hot air didnt damage the fan.

Fonzie

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as long as the fan isnt sucking air RIGHT up next to the bulb your fine.. the fan can take hot air like on very hot summer days.

Ok now I'm setup.Gonna make a test run tonight to check temps. Here's my final setup. 400 watt hps/mh cool tube w/ reflectors. 6in. 130cfm duct fan for cool tube.4in.air scrubber w/ 190cfm inline fan sitting outside on top of tent. Filter is inside tent at top. Tent is growlab GL120 3'11"x3'11"x6'7". DWC 2 ten gallon units. 3 plants each. What u guys think.

pull the air through the light.

always pull the air, it is more effecient.

with enough exhaust you should not need a fan on intake. just open up the holes and put filters over them. i would run intake tubing to get fresh outdoor air. use the light exhaust to heat your house or vent it outside also to keep temp down.

if adding filter on exhaust get a fan that pulls at least twice as much air as needed, the filter will really slow down the amount of air the fan can move.

my 10 cents.

I'm not sure if my cooltube is completly air tight. If it leaks I will be pulling odor out of the room thru the light. I can't have any odor leaks. Security is a big issue with me. If I push air across the light, no odor leaks and I will keep the hot air away from the duct fan. I'm not sure if cooltubes are completly sealed. Anyone know???

You're discussing two seperate configuration options here.

1. Seperate light and filter fans. Best option. CFM on the light is irrelevant. As long as you are pulling cool air over the bulb and exhausting the hot air outdoors, 100 cfm will be enough. If you're pulling 90 degree air, it won't be doing much cooling for you even if it's 500cfm. The filter should be running off a large inline. Attach the inline to this controller: http://aeroponicsnmore.com/climate-control-ventilation-c-23_5/temp-2v-fan-speed-control-variable-idle-setpoint-p-181 That will run the fan at idle speed until it gets too hot in the tent, then it will speed up to max cfm. Attach a water-cooled heat-exchanger over the outlet to cool that air and pump it back into the tent. Add a Co2 bottle, and viola!

2. Single fan for light and filter. This option does not allow you to take the light heat out of your grow area, unless you are running both light and filter exhaust outdoors. This option requires a seperate fan for fresh-air intake, but Co2 is not required.

Ok I've done test run w/ light and all fans running. Room stayed at 73. Tent was sucking the sides in a bit so I opened the 3 passive intakes at the bottom of tent. Is this ok?? Also I decided to push the air across the light and I'm using insulated duct. Cooltube is cool to the touch AWSOME!!

73 is awsome man you can grow some nice buds in that kinda temp if you can keep it like that!