Aerator

I was wondering if anyone had ever used a fish tank air pump to aerate there wort. I was planning on getting a fish tank air pump, tubing, a HEPA filter and a fish tank stone to aerate my wort for an upcoming Imperial IPA. Anyone ever done this?

There are kits with exactly these components available. It's what I use.

Make certain you get a stainless steel 'stone' for ease of cleaning.

i've got one and they work great. i leave mine in for a good 45 minutes, more with high gravity and they get plenty of o2. makes the yeastees all happy and active

Has anyone ever used a regular stone for a fish tank instead of one of those expensive steel ones?

I've only used the cheapies. They're cheap enough to use a new one on each batch but it shouldn't be any harder to sanitize than the stainless one.

DeathBrewer said:

i've got one and they work great. i leave mine in for a good 45 minutes, more with high gravity and they get plenty of o2. makes the yeastees all happy and active

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when you leave it in so long.. do you put a cap or something on the carboy so it is not exposed to the elements? or do you not worry about it.. also.. do you move it around or just leave it in one place?

aekdbbop said:

when you leave it in so long.. do you put a cap or something on the carboy so it is not exposed to the elements? or do you not worry about it.. also.. do you move it around or just leave it in one place?

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As long as it is running, there will be serious positive pressure in the carboy - nothing is getting in there.

On the other hand...

Do you need a hepa filter? I have the pump, tubing and stones but no filter. I wasn't gonna bother but now am wondering...

aekdbbop said:

when you leave it in so long.. do you put a cap or something on the carboy so it is not exposed to the elements? or do you not worry about it.. also.. do you move it around or just leave it in one place?

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i move it around a little, not really sure if that helps, tho. i cover it in saran wrap and sanitize everything (cept the hepa filter, of course, which can't get wet). works like a dream.

i really want to get some o2, tho. then i could do it in minutes :rockin:

thats what I use! standard tank pump>hose>stainless stone (although I have used a regular tank stone many times with no problem) I have yet to do it filtered. I always mean to grab one but never do. FWIW I've never had an infection.

where do you get the stainless stone? I bought one of the regular stones but realized after I took it out of the package that it looked like a bunch of colored sand glued together. There were grains of sand falling of of it like crazy... no way I'm putting that in my beer

http://www.midwestsupplies.com/2-micron-stone.html& http://www.midwestsupplies.com/carbonating-stone-with-1-4-barb-0-5-micron.html but most other online suppliers have them too

If you are just now buying equipment, why not buy an oxygen kit? It's about $50 plus about $10 for a oxygen tank every 10-20 batches.

I'm just saying, if you are going to spend the money, why not have buy something so that it takes 60-90 seconds instead of 45 minutes? And then you also don't have to be concerned about the fact that some people say you need higher oxygen than is possible with an aquarium pump.

I got an oxygen set-up. I'm not completely convinced it has made a difference for me but I never have to give a thought as to whether I gave the yeast enough oxygen (unless it's a huge beer, but that's another story).

I hate to say this but...O2 or GTFO...

The deal is you can shake it, venturi it, aerate it with a fish tank pump, use a funnel and "splash it" and the result is about the same.

Yeast LOVE O2 and it takes 45 seconds of O2 through a stone to reach ppm levels higher than all the above and well into the range that is the best for the yeast.

IMO if you already had a stone and pump then sure it is cheaper but an O2 kit is $50. Getting all that equipment is going to run REALLY close to that anyways.

BTW for a GREAT article on yeast and O2 levels head over to the Wyeast web site and search "aeration". GL

This is what I just got:

Zamial said:

I hate to say this but...O2 or GTFO...

The deal is you can shake it, venturi it, aerate it with a fish tank pump, use a funnel and "splash it" and the result is about the same.

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That's not true, because you can run filtered air for a long time (2 hours) or multiple times while the yeast is reproducing. Some of the O2 will get consumed during that time and it will be replaced with more O2.

Running filtered air forever will not increase oxygen levels in the wort because they max out as a result of the 21% oxygen in air.

I don't remember all the possible levels of oxygen by using different means for oxygenation off the top of my head but they are in 'Yeast' and on this site elsewhere.

I suppose you could add more air later but I've never heard of that being done. I have added pure oxygen once (on my last batch) but this was on a 1.100 beer. It is suggested to add oxygen with big beers at pitching and at 12-18 hours after pitching (after a replication cycle) but I've never heard of adding air. I guess it could be done? But it still doesn't solve the issue that the wort would be under-oxygenated at pitching.

One last thought... I suppose you could keep adding filtered air while reproduction is going on (as you suggested). You'd have to make sure that the fermenter is otherwise closed to room air while doing so unless you are in an environment that is clean enough for open fermentation.

But then, when do you stop it? Too much oxygen once it is not needed and you've just oxygenated your beer rather than your yeast....

ayoungrad said:

But then, when do you stop it? Too much oxygen once it is not needed and you've just oxygenated your beer rather than your yeast....

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On Brew Strong, they've suggest running filtered air for 1 hour after pitching and then 1 more hour about 24 hours later.

They have also said that getting the correct amount of O2 for the yeast is something that is difficult even if you have pure O2. Do you run it for 45 seconds or for 52 seconds? All yeast acts differently, and so everybody needs to make adjustments for each recipe until you get it right.

Because of the speed that the O2 is introduced with pure oxygen, you are more likely to significantly over or under aerate.

LVBen said:

That's not true, because you can run filtered air for a long time (2 hours) or multiple times while the yeast is reproducing. Some of the O2 will get consumed during that time and it will be replaced with more O2.

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Huh? That sounds like the best way to accidentally OXODIZE your beer I have seen. I am of the school of thought O2, then pitch, then wait not o2, pitch, add more o2, and wait. It sounds OK to try but it seems risky to me, if it works for you maybe it is worth a write up...

As I said before I am not a yeast guru or expert. I am not a biochem or microbio tech either! I got my info from one of the best place I could think of Wyeast... as seen here: http://www.wyeastlab.com/hb_oxygenation.cfm

Wyeast said:

It was concluded that pumping compressed air through a stone is not an efficient way to provide adequate levels of DO. Traditional splashing and shaking, although laborious, is fairly efficient at dissolving up to 8 ppm oxygen. To increase levels of oxygen, the carboy headspace can be purged with pure oxygen prior to shaking. The easiest and most effective method remains injecting pure oxygen through a scintered stone.

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Case 1 (pure O2):
Increase O2 to 12 ppm.
12 hours later: down to 8 ppm.

Case 2 (filtered air):
Increase O2 to 8 ppm.
12 hours later: down to 4 ppm.
Increase O2 back up to 8 ppm with filtered air.

Please explain the difference between case 1 and case 2!
Do you actually think that the 8ppm of O2 remaining in the liquid at the 12-hour mark in case 1 is any different than the 8ppm of O2 at the 12-hour mark in case 2?

Is doesn't matter if you add all of the O2 at the beginning or if you do it over a period of time during fermentation. All that matters is if the yeast has O2 available and that the yeast uses up all of the O2 before they are done fermenting.

LVBen said:

Case 1 (pure O2):
Increase O2 to 12 ppm.
12 hours later: down to 8 ppm.

Case 2 (filtered air):
Increase O2 to 8 ppm.
12 hours later: down to 4 ppm.
Increase O2 back up to 8 ppm with filtered air.

Please explain the difference between case 1 and case 2!
Do you actually think that the 8ppm of O2 remaining in the liquid at the 12-hour mark in case 1 is any different than the 8ppm of O2 at the 12-hour mark in case 2?

Is doesn't matter if you add all of the O2 at the beginning or if you do it over a period of time during fermentation. All that matters is if the yeast has O2 available and that the yeast uses up all of the O2 before they are done fermenting.

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I see your point. But there IS a difference between the two... The pure oxygen was double the concentration at 12 hours compared with the air.

Does it make a difference? I have no idea. But Jamil and the founder of White Labs wrote 'Yeast' (which seems to be accepted as the go to source for yeast information) and that book touts pure oxygen.

But, maybe your idea is a new one or one that they did not consider. And maybe it works as well as oxygen. Maybe not.

Keep us up to date. Especially if you can somehow get side by side results of oxygen versus this air pump method...

The concentration isn't the important part. The important part is that the yeast gets the correct amount of O2. 12ppm at the beginning compared to 8ppm at the beginning with 4ppm added later is virtually the same amount of O2.

I'm not saying pure O2 is bad. What I am saying is that you can get the same results with an air pump as you can with pure O2, and in both cases, you need to take care to make sure you give the yeast the right amount of O2.

I'm not making this up. They said this in one or more episodes of Brew Strong.

First post everyone. Plus I am new to this whole thing. So feel free to correct me if I'm wrong. That said I have been reading up in a couple of different sources, plus I intern for a company that is analyzing the rate of yeast activity for SABMiller and from that I have drawn a few conclusions and want to put in my two cents.

What happens after pitching the yeast is it uses up all the available oxygen during a period of reproduction. We aerate so that there is ample amounts if oxygen dissolved in the wort for the yeast to use. Once all of the oxygen is used up then the yeast begins to ferment the sugars and reproduction essentially stops. If more oxygen is added later then the reproduction starts back up.

For the high gravity worts the second aeration makes sense because there are large amounts of fermentable sugars and increasing the amount of yeast will keep your fermentation timeline reasonable. On normal gravity worts a second set of aeration is unnecessary And can do weird things to the fermentation process and is risky.

Now for the original argument of O2 or air. The fact of the matter is, O2 gets the job done quicker reducing the opportunity for the wort to get an infection. But in either case you are dissolving oxygen in the wort. However, because using O2 is so much faster you can easily overoxygenate which can lead to too much yeast reproduction and an overabundance of fermentation byproducts. Thus resulting in off flavor in your beer. This is also why you wouldn't want to aerate a second time for a normal gravity wort.

I guess if I had to pick one method over another I'd say pure oxygen is better but I'd get a dissolved oxygen meter so that I could make sure not to over oxygenate the wort.

Listen to The 06-27-11 "Aeration" episode of Brew Strong. http://www.thebrewingnetwork.com/shows/771

Listen starting at 35:18
Jamil: "Aeration using air.. and again you are limited to 8 or so ppm. The solution is what? Using pure O2, right?"
John Palmer: "Right... OR leaving that air on longer."

Then they discuss how you can sustain the 8ppm for a longer period of time (Basically, replacing the used up O2 with new O2.)

... Then at about 36:40, John Palmer goes on to say how he pre-aerates the wort, pitches the yeast, and then hooks up an aquarium pump for 30 minutes for good fermentation at higher than typical gravities.

Also, on one of the 4 High Gravity Brewing episodes, they mention re-aerating the wort 12 and 24 hours later, but I'm not going to go through all 4 episodes to try and find it.

I say, if it works, do it. Either method. FWIW, reoxygenation (with oxygen) for high gravity beers is what they say in 'Yeast' as I mentioned above.

But for me, I go with oxygen. If I had to choose, I would rather over-oxygenate han under-oxygenate and for normal gravity beers, it doesn't get any easier than 60 seconds of oxygen and done... seal the fermenter and wait until it's done.