i do not want to trim any more ....how the hell do u do it

whitebb2727 said:

I always over size. I run a 8 inch on a 4 inch fan. Its over kill. The bigger the better.
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Fogdog said:

When sizing my oven vent fan, I read that ventilation experts size the ducting according to fan air velocity. Matching air velocity to duct diameter is to enhance linear air flow in the duct. From my understanding, oversizing the duct-work reduces efficiency due to eddy currents inside the duct. I wouldn't mind being told why this is wrong.

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whitebb2727 said:

You are absolutely correct. This situation is a bit different. The run is so short it makes little difference.

Match the duct. Oversize the filter. The bigger the filter, the more surface area you have and the slower the air moves over it. It allows more time for the carbon to scrub the air.

I'm not after efficiency of air flow. I'm after smell reduction.

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curious2garden said:

LOL I don't know how you guys grow in that kind of humidity without powder mildew.

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Fogdog said:

thanks, I just learned something. It's all about the objective you are trying to accomplish.

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ANC said:

If you spend a bit more, you can get medical grade carbon flakes that can take many times as much shit out of the air before it is spend.

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Philip-O said:

Do you know of a good source for these carbon flakes?

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whitebb2727 said:

Do a search for bulk coconut carbon. I bought mine from an online hydro shop.

Several vendors will pop up. Get coconut not coal based.

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Philip-O said:

Great, several sources right away. Do you care to comment why coco based is preferrable?

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