What size fan/filter
- Thread starter tommyb88
- Start date
Hey TommyB88. Go to this forum and check it out, they are having a convo about filters and what not. You can read up there and ask your question. Ppl that know better then I do CLICK LINK ------> Carbon filters? 
Muttt
New Member
Are those inches or CM ?? Here's the rule of thumb I used. You want your fan/filter CFM to be 3 times the cubic feet of your area. So, my grow box is 72 cubic feet. So, I would need a 250 CFM to get the air exchange that would be desired. Hope that helps.
I was going to say 400cfm just didnt want to give wrong info since i dont use them
- Thread starter
- #5
CFM is correct dude!
Muttt
New Member
400 would be just fine. 250 would be the minimum. I actaully have a 500 CFM fan/filter on my box. But, I only have 72 cubic feet of space .... LOL. Needless to say, I don't have to run it at 100%
Fuzzy Duck
Well-Known Member
Some calculations mainly cubic meters tho... american measurements are based on an imperial system, where as in europe based countrys metric will prevail...
1. To determine the ventilation required in m3/hour, multiply the area of the room (m2) by 125. For example a grow room of 5m x 2m = 10m2 so the required extraction rate would be 10 x 125 = 1250m3/hour.
2. To calculate the size of fan you require simply follow these instructions:
Measure the Height, Length and Width (in metres) of the growing environment.
Multiply together (H x L x W) to give the cubic meter volume.
Multiply this figure by 20.
This is the size of fan required to change the air 20 times in an hour
1. To determine the ventilation required in m3/hour, multiply the area of the room (m2) by 125. For example a grow room of 5m x 2m = 10m2 so the required extraction rate would be 10 x 125 = 1250m3/hour.
2. To calculate the size of fan you require simply follow these instructions:
Measure the Height, Length and Width (in metres) of the growing environment.
Multiply together (H x L x W) to give the cubic meter volume.
Multiply this figure by 20.
This is the size of fan required to change the air 20 times in an hour
Fuzzy Duck
Well-Known Member
More likely be ok with a 4 inch inline fan pushing 5 inch depending on m3 per hour.
I believe your tent currently requires a fan which does 108m3 per hour.
Bit hard to recomend kit... as some times brands are only aviable in one country or another... if europe based - wolfnados 2 speed fan gets my vote, Systemair RVK fans are pretty alright.
Muttt
New Member
Just make suer your CFM of your fan doesn't exceed the CFM of your filter. Your filter should have a higher CFM than your fan ... if possible. If you try to run 200 CFM of air through a 100 CFM filter it won't work efficiently and will allow odor to get through.
- Thread starter
- #11
- Thread starter
- #12
been looking around and can any of you tell me the difference between these 2 apart from the PRICE! arnt really sure as im new to fans and filters but they look pretty much the same to me, would prefer spend the extra if i no im getting a decent kit but is there any point when i can get 1 for near enough half price as theres loads going on ebay, here they are
Value Fan & Filter Package - Green's Horticulture
4" Carbon Filter, In Line Fan & Duct Kit - £49.99
Value Fan & Filter Package - Green's Horticulture
4" Carbon Filter, In Line Fan & Duct Kit - £49.99
- Thread starter
- #13
Fuzzy Duck
Well-Known Member
Greens hortic is really expensive...
I'll PM ya link to cheaper hydro shop or 2
I'll PM ya link to cheaper hydro shop or 2
Fuzzy Duck
Well-Known Member
Well in theory yes, but using 2 fans may create negative pressure bit like sucking the air out of crisp packet effect... thats mainly when using 2 fans of equal size thats when dual fan speed control comes into play to regulate fan speeds.
At a push you can use 1 large fan & 1 smaller fan to off set negative pressure.
Negative pressure only really happens in near total sealed growing enviroments, provding ya got a passive opening ya be more less ok.
Most of us get away with passive vent based at the bottom of grow tent, so as the exhaust fan takes warm air out the passive vent draws in new fresh air.
I'm not total sure if the Ds/Dr60 basic model has little windows/velcro flaps near base of tent or not, if it has those are ya passive intake
When growing indoors the house hold will have an ambient temperature whether that by in summer months or in winter when using central heating, this all effects ambient base line temps of grow tent !
Theory does suggest that the more air you pull through the growing enviroment the cooler the temps will be ! its a fine line to draw...
- Thread starter
- #16
Fuzzy Duck
Well-Known Member
Muttt
New Member
What it really boils down to is what quality is the carbon inside the filter. The shape, color, length etc aren't really important.
Blow the air out and use a passive intake. It's the way that causes the least amount of problems. If you don't have some kind of negative pressure inside the cabinet, you'll be pushing stink out through every little leak, crack or opening.
Blow the air out and use a passive intake. It's the way that causes the least amount of problems. If you don't have some kind of negative pressure inside the cabinet, you'll be pushing stink out through every little leak, crack or opening.
Fuzzy Duck
Well-Known Member
I took a 2nd look at this & done a quick search on brand name...
It appears this model of fan basically an inline exhaust fan design for bathrooms, so ye it will work in a grow tent where humidity could be on par with bath rooms 'n' all the electrics should be safe.
How ever ya more than likely need to wire a plug into it, might even come with a pull cord or switch tho to turn the fan on ?
Not to sure if was designed to run 24/7 tho for very long periods... ? don't think it will be a problem tho lots of peeps leave bathroom inline fans running for awhile or even forget to turn em off.
- Thread starter
- #20
thanks for the quick replys and after a lot of reading on the internet iv decided spend a bit more and go with the rvk as there built to last and read the cheapo ones you can purchase off ebay are prone to breaking quite often, id prefer spend the extra and have piece of mind and will work out cheaper in the long run, as for filters im going av a read up on the best carbon you can purchase and get one with that maybe rhino, thanks for the help every1
Similar threads
