Ventilation advice needed please

cannn said:

Interesting idea oversizing the filter but ive never seen a problem using the right size filter. And also using hps would recommend you change out the air more than once every 3 minutes.

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Using an hos wouldn't require changing more than every 3 minutes. That's what every grow calculator I've seen reccomends.

The reason they want you to match the filter to the fan is to buy more filters. A larger on3 filters better and lasts longer.

Where did you get the info for more than 3 times for his?


I do a lot of things people say not to do. I rebuild and refill my filters. I bake the carbon to reactivate it.

It is illegal here and been put to the test by cops being near my exhaust a few times.

The 600W is capable of covering 1 sq meter, why not scrap the reflector, hang the bulb vertically, grow four plants (or more) around it about one meter high?

Running the lamp horizontally only gives you 1 sq meter, running the lamp vertically can increase that four fold.

As far as extraction, for that volume I'd use a fan that is capable of 300 CFM, preferably 6" diameter duct. I'd used an intake fan and prefilter as well, around 150 CFM would work for that.

Filters can be made with simple supplies from the hardware store and aquarium shop, I've never purchased a commercial filter and no one has ever smelled my ops.

cannn said:

I got the info from doing grows without ac. The heat output of the hps in my setup can be too much even with my air cooled hood. The air in my tent probably changes out 3 times a minute and still rises 8-10 degrees going from my room into and through the tent. Its 76 ambient temp in my house all the time and generally 85 in my tent with a 400 watt hps and my ventilation

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If you bring the ambient temp down it will help, it costs more though.

Is your hood pulling air from inside or outside?

Does the hood exhaust inside or outside?

whitebb2727 said:

Using an hos wouldn't require changing more than every 3 minutes. That's what every grow calculator I've seen reccomends.

The reason they want you to match the filter to the fan is to buy more filters. A larger on3 filters better and lasts longer.

Where did you get the info for more than 3 times for his?


I do a lot of things people say not to do. I rebuild and refill my filters. I bake the carbon to reactivate it.

It is illegal here and been put to the test by cops being near my exhaust a few times.
View attachment 3977269

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With my setup, air being exchanged at least 3 times per minute probably more like 5, i still see a 5 degree rise in temperature from outside to inside the tent. Id see much more with the setup you describe

Enigma said:

If you bring the ambient temp down it will help, it costs more though.

Is your hood pulling air from inside or outside?

Does the hood exhaust inside or outside?

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Hood exhausts outside. And pulls air from inside the house but outside the tent. Im spending too much on ac as it is. It gets up around 90 pretty often where i am around this time of year. Its literally supposed to be above 90 as the high the next 9 days

Sorry for the change in my air temp change lol im a lil baked and the ac was turned off it got extra hot in here and i read the temp dif wrong since it got up to 82 in here. Its a 5 degree fahrenheight change

cannn said:

With my setup, air being exchanged at least 3 times per minute probably more like 5, i still see a 5 degree rise in temperature from outside to inside the tent. Id see much more with the setup you describe

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How many cfm is your fan?

It won't hurt to use more cfm. That was the minimum requirement.

whitebb2727 said:

How many cfm is your fan?

It won't hurt to use more cfm. That was the minimum requirement.

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424, so working at full power with no obstruction it would exchange my space 8 times per minute. With that filter id say probably 3-5

Have you thought of using a 400w in the summer time?

Enigma said:

Have you thought of using a 400w in the summer time?

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400w is all i use

Did i forget to say that? My bad griff is the one with the 600

I must have misread or was confused, Cherry Skunk will do that.

You can build a cooler for the tent:

Box fan
Automobile radiator
Hoses
Reservoir
Water pump
Chiller

You get the idea, power cost will go up significantly, I'd insulate the lines and reservoir.

cannn said:

Theres a like button on these posts.. Lol sorry i usually dont care but im 3 likes short of being a well known member and ive been striving for that title literally all last night and this morning advising ppl

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We're running 1K these days. The girls lurv it!

P.S. 3 likes short?

There ya go

roseypeach said:

We're running 1K these days. The girls lurv it!

P.S. 3 likes short?

There ya go

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1k sounds like the best but from what i understand 600 watt hids are the most efficient in terms of lumens per watt. Idk how significant it is though.

And thank you!!

cannn said:

1k sounds like the best but from what i understand 600 watt hids are the most efficient in terms of lumens per watt. Idk how significant it is though.

And thank you!!

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The 600 is the way to go, if you can accommodate it.

cannn said:

1k sounds like the best but from what i understand 600 watt hids are the most efficient in terms of lumens per watt. Idk how significant it is though.

And thank you!!

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Depends mostly on what you've got underneath. We run 2K for 4 and pull 6-7 lbs.