Dankinbank

How many times per minute ,minimum, do you need to refresh the air of your flower room? Once per minute?

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Dankinbank::
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GreenDragon2k

CFM requirement depends more on lighting than the size of your space. So instead of calculating by size and times per minute... Just divide your wattage in half and you'll get the approxamate required CFM...

So if you've got a 400w HPS then you'll need at least 200 CFM of exhaust.

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Dankinbank

OHHH mainly to take care of heat, it's not a matter of supplying that much fresh air to the plants? thank you for the formula

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Dankinbank::
Organic fertilizers should be the new currency.

Freakshow68

I have a 10x12 room, currently running a 1000 watt HPS in a cool tube. My stanley blower running on the lowest setting - roughly 950-1200 CFM. The room has a concrete floor and my basement is not heated, but the room runs around 74-75 degrees with lights on

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tripps

Cool, never heard of that ratio, but I done good on accident. I run 2200w (formerly 2000w) and I run 1000 cfm. In a 250 cf room that's 4 times a minute, but my room is really small for what I grow, more like a giant cabinet. Plus AC

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Dankinbank

I should have expressed this in the original post, but if i'm using 600 watt HPS with a vented hood/reflector, would 200 still be enough?

PS Freakshow. How is the noise on the stanley blower?

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Dankinbank::
Organic fertilizers should be the new currency.

Freakshow68

well, you can hear it. LOL. it's not terrible but pushing that much air through 6 inch vent tube does make some noise. When the blower itself is very very quiet though. About the only sound you hear is from the air going through the ventilation ducting

__________________
You cannot help the poor by destroying the rich.
You cannot strengthen the weak by weakening the strong.
You cannot bring about prosperity by discouraging thrift.
You cannot lift the wage earner up by pulling the wage payer down.
You cannot further the brotherhood of man by inciting class hatred.
You cannot build character and courage by taking away people's initiative
and independence.
You cannot help people permanently by doing for them, what they
could and should do for themselves. - William J. H. Boetcker