Fish Tank Pump

[Xiren]

I have heard about using a fish tank pump to aerate your wort and letting it bubble for no longer than 30 min. Wouldn't that give it an infection or make it more possible to get infected?
Thank you in advance.

 

[fifelee]

You should us an in-line filter to prevent infection.

http://morebeer.com/view_product/16607/102281

 

[Xiren]

Right. I was just worried that for 30 min there would be nothing protecting my wort and I do not want to get any nasties.

 

[Iordz]

I would suggest letting the pump run for an hour, so you can get as much o2 as possible, remember you are pumping air and air is only 20% oxygen. I'm going to invest in an oxygen system, it wil save some time.

 

[Xiren]

Where should I look to find O2 tanks and a refiller?

 

[Iordz]

I found tham at Home Depot, about $7 for one of those small red tanks. They are disposable, so you have to buy new ones, the only way to get refills would be to buy a 5lb tank, usually green, and refill it at the welding supply store.

 

[Xiren]

That does sound better than spending $30 for a fish tank setup and taking 30-60 min when in 15 seconds, one could pitch the yeast.
Thanks a ton Iordz!

 

[eddie]

Where should I look to find O2 tanks and a refiller?

The Bernzomatic oxygen tanks that you get at the hardware store work just fine. You'll need a left hand threaded valve to fit it though.

 

[abracadabra]

You can help prevent infection by simply covering your wort while you areate.

Hepa filters can be purchased or air filters are easily made using a tube filled with moist cotton balls with rubber stopper at both ends or making one out of PVC pipe.

With just a little bit of planning the time it takes for the wort to areate using an aquarium pump can easily be used cleaning up the boil pot, MLT, and other equipment, disposing the spent grains and putting your equipment away.

1 hour is not a hard and fast rule and the amount of time it takes depend on any areation you do (such as letting the wort splash into the fermenter) and the size of the pump and amount of air your aquarium pump can move, ie small pump longer time, big pump shorter time.


Another plus of the aquarium pump is the HEPA filters are cheap and so are cotton balls.

Many O2 kits come with HEPA filter and many people add them if the kit doesn't come with filter.

Also you can areate your wort simply by letting the wort splash into the fermenter, draining it thur a screen, shaking the fermenter or by using a combination of or all of the above methods.

O2 works fine and quickly but it's also a recuring cost around $12 a bottle in my neck of the woods, where the aquarium pump is basically a one time purchase.

I'm not trying to discourage you from getting an O2 bottle just offer a different perspective.

 

[Funkenjaeger]

One difference is in the amount of oxygen you can get into solution. Pulling some numbers from:
http://byo.com/mrwizard/1128.html

Fact: Wort has an oxygen content of about 8.5 ppm when saturated with air (79% nitrogen and 21% oxygen) and an oxygen content of about 43 ppm when saturated with oxygen.

Not only do you have to spend 15-30 minutes with an aquarium pump to saturate the solution, you also only get about 20% of the amount of oxygen in the end. I have an O2 system instead of an aquarium pump system not because I really care about the time issue so much, but because according to figures like these, it does a much better job, and I figure if I'm going to aerate I might as well do the best job I can, within reason.

With that said, at the end of the BYO article he states that while he uses pure O2 for yeast starters, he still uses just air for aerating wort in the fermenter, so obviously there's plenty of reason in either case.