Air Filters

[sah]

I've seen a few ideas and contraptions for filtering air from an aquarium pump before it gets to a diffuser stone or similar submerged in wort.

1. Cotton wool dampened in sanitiser and stuffed into a tube with stoppers at both ends that allow the air line to be poked through. I think I first saw this in John Palmer's How To Brew.

2. A closed jar of sanitiser with a submerged diffuser from the pump and an air line picking up the filtered air from the head space of the jar.

3. A commercial product that appears to be a disc shape that I know little about?

If you aerate your wort with a diffuser stone how do you filter the air? Are you happy with it?

I'd like to hear some details about the 3rd option?

Thanks in advance.

Scott

 

[Zwickel]

Hi sah,

Im using an injection filter, you may buy at any pharmacy.
It is a 0,2m bacterial filter for syringes, cost only a few cents.

look at it here:

 

[lonte]

Do I understand that the above is a tee-piece, the wort runs through the line and air is sucked into the line through the filter ??

 

[Zwickel]

Do I understand that the above is a tee-piece, the wort runs through the line and air is sucked into the line through the filter ??

[post="124068"][/post]​

thats right. Because after whirlpooling and cooling, the wort runs through a small window down in the cellar of my house into the fermenter, it sucks air through the filter. Is a perfect passive airaiting. For that Im using a thicker tube.

To produce a starter, Im using the filter that way:

 

[PistolPatch]

I'd like to hear some details about the 3rd option?

[post="124008"][/post]​

Hi there Scott. The air pump I use for aeration is pretty small and won't work with the bacterial filter (you can hardly suck through the filter with your mouth.) So, depending on your pump, this may not even be an option for you. The other question on using these filters is how many times can they be used before they degrade or become clogged? I have never found an answer on this.

Currently, I use no sort of filter and I can't see this being any worse than pouring from a height into the fermenter especially if you pitch your yeast pretty quickly.

I reckon number 2 is a great option and I will re-build the current flimsy version I made in about 2 minutes (which leaks hence me using nothing at all at present) now that I have some aquarium sealant. This option, once built, requires nothing extra though I must say Zwickel's set-up looks very impressive.

 

[Zwickel]

(you can hardly suck through the filter with your mouth.)

Hi PP,

this happens only when the filter becomes wet!

as long as the filter keeps dry, there is only a little resistance.

If you live in a dusty area, you may use a pre-filter, made by coffeefilter for example, to avoid the bacterial filter will be clogged by dust.

That way you may use the filter many times.

Cheers

 

[Hoops]

I'd like to hear some details about the 3rd option?

[post="124008"][/post]​

The other question on using these filters is how many times can they be used before they degrade or become clogged? I have never found an answer on this.

[post="124152"][/post]​

I use the same type of filter in my setup and mine lasted me around 9 months from memory. I now also use a small pre-filter which will help it last longer and work better.

Hoops

 

[PistolPatch]

Zwick, unfortunately my filter is dry and I still can hardly blow through it. It came from Grain and Grape but perhaps I received a dodgy one? Maybe someone else here has the same one and has had better results (it has the yellow ring around it). Mine is about 20 times worse than the old breathalysers - if you could blow through those, you were definitely sober!

(Thanks for the feedback on their longevity, Hoops. 9 months sounds pretty good.)

 

[pint of lager]

The filters from G&G are 0.2 micron and offer alot of air resistance. My cheapie big W fishtank pump manages to pump against the resistance of the air filter and 2 micron ss stone. It wouldn't cope with any further resistance.

Do not get any moisture on the filters, or they become permanently blocked once the moisture dries. They are fine on the day that they become wet, but the next time you try and use them, they are blocked.

 

[pint of lager]

In answer to Sah's question, I use an air filter from G&G. I decided some time ago, if I was going to the effort of running an ss stone and airpump, it wouldn't take any extra effort to plug an inline air filter in too.

 

[Doc]

Another tip is to smell the air that comes out of the filter (ie. disconnect from your airstone and breath in the air).
I did this on my previous brewday and the filter was OFF. The air was BAD. Replaced filter and all was good. Must have been using it for 6 months or so, and as my beers have been OK, I must have caught it in time.

Doc

 

[Vlad the Pale Aler]

Wrap the pump in a few layers of paper kitchen towel and give it a squirt with a safe sanitizer, preferably ethanol.

 

[JSB]

geez - not that much of an issue...pitch the right amount of healthy yeast...and you will be on top of your bacteria fighting game..

Cheers
JSB

 

[sah]

I've just been given a 0.45 micron syringe filter to try.

See here http://www.millipore.com/catalogue.nsf/docs/SLHP033NB

That should knock out most dust and spores?

Scott

 

[sah]

This filter didn't work so good with my pump. Its a two port delivery pump (from Ross) and I'm guessing that the increased resistance from the filter encouraged most all of the air out the other delivery. I didn't have it blocked.

Has anyone had this problem and worked around it? Perhaps by blocking the delivery not in use?

Cheers
Scott

 

[doglet]

Go to BigW or similar store and go to the pet section. Buy a cheap aquarium tubing/fitting kit that comes with a T-piece. Price is around $5 or so.

Then you can use both delivery ports on the pump and feed them into one tube with the T piece.

I found a kit that also had a one way valve that I have installed between the air filter and the aeration stone - it was in the kit so I thought why not!

 

[Sloth]

sah,

the 0.45micron filter might be good for dust and things but bacterial spores go as small as 0.35microns. If you were going to go to the effect, my opinion would be to use 0.3micron or smaller.

Sloth.

 

[sah]

Thanks for the information Sloth. I thought bacteria generally had to be carried by something though, such as dust. Do bacteria often become suspended in air and carried in currents like fungal spores?

thanks
Scott

 

[Sloth]

sah,

not sure on that one but if they do then whats to stop bacteria from entering the filter by being carried on dust and things and then finding their through the 0.45 micron filter and into your beer??

Im currently in the process of looking for some filtering method. John Palmer mentions the use of HEPA filters in his book and as you can see Zwickel uses this. I have had a look in one pharmacy but they didn't have any so i guess the search continues....

Cheers, Sloth.

 

[Darren]

sah,

the 0.45micron filter might be good for dust and things but bacterial spores go as small as 0.35microns. If you were going to go to the effect, my opinion would be to use 0.3micron or smaller.

Sloth.

[post="126113"][/post]​

0.45 micron should be good enough for beer spoilage organisms. Your main worry will be wild yeast 4-8 micron in size. Small spore organisms GENERALLY dont spoil beer.

cheers
Darren