Help needed with size of filter/fan

My room is about 6ft square with a sloping ceiling so I'll have a growing area about 6ft x 3ft - will have about 4-6 plants eventually. Question is, what size filter/fan set-up will I need? I presume 6 inch fan, but wanted to check on here first. I want zero smell leaving the room as we have neighbours. And if I go 6 inch fan am I best to bite the bullet and get a Rhino filter (300mm or 600mm?), or will a DIY homemade one be nearly as good?

And should the fans be on a temperature control or is it enough for the fan to just run when the lights are on?

I run a fan all the time when the lights are on and intermittently when they are off. Totally depends on you humidity etc. HTG supply sells a 6" carbon for about 100 bucks that works great. How close are your neighbors? like apartment-wall-close or house-next-door-close? because if they are apartment close you need to pay close attention to what you get for a fan because a lot of them are pretty noisey. What kind of light? what kind of hood?

Neighbour is detached so no big problem there, going for LED panel so low heat. So do you run a fan when the lights are off for heat or smell removal or to control humidity?

The main purpose is to eliminate smell/bring in fresh air, but it also works wonders at maintaining humidity. If you shut your fan off during lights off, your RH can jump up to the high 90's - but this also eliminates fresh air from being pulled into your space.

Run your exhaust fan as much as possible if all other factors are optimal.

Good stuff, cheers chaps. Any more input on filter sizes would be great

Welcome!

I'd highly recommend a 6" inline fan with a speed controller. A good buy would be a 6" Vortex inline fan and a Speedster fan controller. That way you will be able to adjust the airflow to keep conditions near ideal in any season. Set it up to suck through the carbon filter then blow out of the room. Keep this running 24 hours a day to maintain negative pressure in the grow space (prevents odor from leaking out), and constantly removes moist, stagnant air that can lead to mold/mildew problems.

As for the DIY filter versus store bought, that one will depend on your security concerns. I have not tried building my own, because I prefer the peace of mind I get from the Phresh filter. When it comes to carbon filters, you really do get what you pay for. A cheap filter may only last through one crop.

Good luck!

Thanks Spicy, that's really helpful, I'll go with the decent quality Rhino filter then, and get myself a fan controller to.

The room will be virtually sealed, so I presume I should cut an intake hole the other side of the room to the exhaust hole to allow fresh air in? And should I put a one way gravity flap plate on it or cover the hole with a piece of carbon extractor sheet to stop any smell leaking out that way?

Make sure the filter can support CFM's 10% higher than what your fan runs at full speed. If it's under or about even then it will have troubles properly filtering the air

Variac based speed controller...

oceanside said:

Make sure the filter can support CFM's 10% higher than what your fan runs at full speed. If it's under or about even then it will have troubles properly filtering the air

Click to expand...

Agreed that if your airflow outruns the filter then it's unable to adsorb all of the odor.

CFM of entire ductwork and all that comes into play also.

It's always good to oversize a filter. Oversizing a fan can be good too since it could always be reduced with a variac.

Speedster controllers sucks. Al rheostat controllers suck for inine fans. Look into a "variac" style speed controller.

Damn youuuuuu Snaps! Upstage me, why don't ya!? lol

About a pound.

Metasynth said:

Damn youuuuuu Snaps! Upstage me, why don't ya!? lol

Click to expand...

Lol. You want the light work?

SnapsProvolone said:

Lol. You want the light work?

Click to expand...

Um...if you're my stage director, I'll go where you want me.

Metasynth said:

Um...if you're my stage director, I'll go where you want me.

Click to expand...

I'm just glad to have other competent members chime in with what I feel is very good information.

Now onward, spread the knowledge! Please don't be boring like I am or like Al Gore on global warming.

having negative pressure in your room partnered with your Carbon Filter will help contain the smell. More air pressure out than in = negative pressure.

Just be sure to first run the exhaust fan with your carbon filter OUTSIDE your grow room, preferably in a bathroom or outdoors if you can. The carbon can get powdery when shipped and "POOF" when you plug it in. Look up some reviews on amazon, there's people who have experienced this and had to spend hours cleaning up the mess lol

Cheers for the tip I've ordered a top of the range Rhino Pro filter, so it should handle the pull the the 6 inch inline fan ok.

Off down the hydro shop on the way home to get some rock wool cubes and some bits to make my hydro seeding/cloning set-up. Tomorrow I'm going to tank out the room with builders plastics, so no chance of any leaks downstairs.

Metasynth said:

Speedster controllers sucks. Al rheostat controllers suck for inine fans. Look into a "variac" style speed controller.

Click to expand...

A variac style speed controller is ideal, but I'm happy with my Speedster. Some fans (Elicent, for example) require a variac, while others (Vortex, Hurricane, etc) can be used with the Speedster. I have both a Vortex and a Hurricane, and I do find the Vortex/Speedster jive better than the Hurricane/Speedster.

So yes, a variac would be ideal if you want to spend the money, but from my experience the Vortex/Speedster combo works just fine.

Definitely need the speed controller.. Your neighbors will think you have a small jet in your closet Phresh makes a good filter. I have read that hanging the fan by bungee chord helps with noise as well as making a muffler.. This is the speed controller recommended for my fan. I am not sure if it is variac though.. Kind of pricey. I saw one on ebay, used for 30 bucks..

http://www.titancontrols.net/products/ventilation.aspx