hi again i need something to filter my passive intakes from outside, does anyone use the cooker hood filters and would you know if they affect the air flow much, and where do you buy these from.
or anyone know anything else i can use to stop the bugs /light getting in/out,
i thought i was ready to grow but it seems i need to make 5x mor passive intakes, dammit

thanks

I use cooker hood filter on my intake in my garage grow - it does seem to restrict airflow a little but also seems reasonably light proof - mine is on the back wall of my grow space which is a couple of inches away from a brick wall in a dark garage... no problems so far.. but I doubt its 100% light proof, but not a problem in my situation - you could always look at putting a light baffle over it.. I just cut a big square that was roughly 4 or 5 times the area of my 4" circular extraction..

You should be able to get it most places like big supermarkets or Robert Dyas/etc..

You do not literally have to have 5 holes the same size as your extract. It is 5 times the area of your extract.

If your extract is a 6 inch fan for example (150 mm) ( which is an area of 0.071m) your intake should have an area of five times that, i.e. 0.355m2. That could be for example, a slot 0.9 long, by 0.4 high (36 inches long by 16 inches high)

I would personally cut a slot half that, and see what happens,

what you need is a light baffle and for a fly screen use a pair of your old tights

E2a Cooker filters vary widely in thickness and density, and that will vary your fan volume flow rate accordingly. I woould just use material from tights, probably wash them first.

Are the carbon cooker filters any good for extraction? do they destroy the smell?

cheers

I use tights and carbon cooker hoods for my passive intakes works great and with the grease filter as well completely blocks out the light in and out!
didnt have the space for light baffles!