Oxygenating pumps

[CD]

For many years I’ve been using this primitive gadget, which has six holes of 1.5mm in it, to bubble a bit of air through my 3ft deep FV after pitching the yeast. The Whisper aquarium pump actually stalls if the weight is too low, which limits it to about 2ft. submerged.

I thought I would go a bit up-market recently and bought a 5 micron sintered stainless steel air stone, but the pump can’t pump any air at all through it. Can anybody tell me where I can get a more powerful aquarium air pump?

 

[aamcle]

Most people use an Oxygen cylinder rather than a pump.

Aamcle

 

[CD]

Sounds expensive.

 

[LED_ZEP]

A cheap option that can be powered off a USB battery pack:

Aquarium Air Pump

 

[CD]

Has anybody used either a Tetra APS 50 or APS 100 air pump in conjunction with a 50 micron sintered stainless steel air stone? Or know whether the 50, with smaller diaphragm, produces more pressure?

 

[kelper]

A car tyre pump or one for inflatables would be less than a tenner. They can be had with various pressure ratings. Have you 12V available?

https://www.amazon.co.uk/Electric-Inflator-Cigarette-Compressor-Basketball/dp/B08CND75C5
It should not overheat if the back pressure is not high. If it seems too high could you tee off and supply more stones?

Aldi, Lidl and many petrol stations sell similar.

 

[Edison]

I’ve just bought my second disposable O2 cylinder, this time from aboutroofing.com for £23 delivered. I have a small regulator (£26) which I modified to fit a JG push fitting which runs 3/8” beer line to a SS wand with a stone on the end from angelbrew. The last cylinder lasted for over 20 brews and only needs a 30s burst. Usually get yeast bubbling away after only a few hours from pitching!

 

[peebee]

Sounds expensive.

They probably are. But a full cylinder will probably last "forever" (forever = till you don't care anymore).

I used to use a 24V lorry/tractor tyre pump; those SS "stones" do need a bit of puff. I got the O2 'cos the pump systems are expensive to maintain (I was using anti-microbial breathing filters which often exploded with the pressure - bet them filters got impossible to get hold of recently - though many won't filter the air being pumped into the beer anyway) and the pumps are pretty noisy and can be running 1/2 hour (in two instalments, 'cos the pump does get hot ). Pure oxygen only needs a 40-50 second blast and is sterile by default.

I wonder now whether "aerating" is at all necessary (if using stir-plates and liquid yeast starters)? The starters are calculated to produce enough yeast cells to ferment the beer; oxygen is only needed to grow more cells and is adequately supplied with O2 by the stir-plate (yeast doesn't bother with oxygen for fermenting - it can, but can't be bothered). So, with a well created starter, is there any need for aeration?

I don't bother aerating sub-1.045 beers anymore, maybe I shouldn't bother for stronger beers? But I have now got a lifetime's worth of O2 so …

 

[kelper]

They probably are. But a full cylinder will probably last "forever" (forever = till you don't care anymore).

I used to use a 24V lorry/tractor tyre pump; those SS "stones" do need a bit of puff. I got the O2 'cos the pump systems are expensive to maintain (I was using anti-microbial breathing filters which often exploded with the pressure - bet them filters got impossible to get hold of recently - though many won't filter the air being pumped into the beer anyway) and the pumps are pretty noisy and can be running 1/2 hour (in two instalments, 'cos the pump does get hot ). Pure oxygen only needs a 40-50 second blast and is sterile by default.

I wonder now whether "aerating" is at all necessary (if using stir-plates and liquid yeast starters)? The starters are calculated to produce enough yeast cells to ferment the beer; oxygen is only needed to grow more cells and is adequately supplied with O2 by the stir-plate (yeast doesn't bother with oxygen for fermenting - it can, but can't be bothered). So, with a well created starter, is there any need for aeration?

I don't bother aerating sub-1.045 beers anymore, maybe I shouldn't bother for stronger beers? But I have now got a lifetime's worth of O2 so …

Oxygen is quite dangerous if stored indoors. An oxygen-rich atmosphere makes anything combustible virtually explosive and a tiny spark can ignite clothing and bedding.

 

[peebee]

Oxygen is quite dangerous if stored indoors. An oxygen-rich atmosphere makes anything combustible virtually explosive and a tiny spark can ignite clothing and bedding.

Aye! And we don't want any reminders of Apollo 1. (Damn … that was a reminder! Oops).

 

[terrym]

What's the point?
Oxygen, unlike CO2, doesn't dissolve very well in water or wort so all you need is a minute or two with a mixing paddle and when you see foam on the top that's it, job done. When the wort is saturated with oxygen, which doesn't take long to achieve, any further effort is unnecessary.

 

[peebee]

What's the point?
Oxygen, unlike CO2, doesn't dissolve very well in water or wort so all you need is a minute or two with a mixing paddle and when you see foam on the top that's it, job done. When the wort is saturated with oxygen, which doesn't take long to achieve, any further effort is unnecessary.

It's okay to say that when you've a nice uncluttered bucket to ferment in. But us rich-kids have daft SS conical fermenters that are way too heavy to give a shake and full of "paddle-fouling" intrusions like thermo-pockets and racking pipes.

 

[Edison]

I can't quite get my hands on the figures, but testing has proved it is impossible to dissolve the ideal concentration of O2 in wort just with atmospheric air. Pure O2 is required for ideal concentrations.
The likelihood of an O2 leak from a disposal cylinder would presumably be very low as it is self-sealing when the regulator is removed and you would need a noticeable leak in a confined space to be dangerous. That said, the cylinder is small enough to be put on a shelf in the garden shed if you were concerned.

 

[Edison]

https://wyeastlab.com/oxygenation/

 

[terrym]

It's okay to say that when you've a nice uncluttered bucket to ferment in. But us rich-kids have daft SS conical fermenters that are way too heavy to give a shake and full of "paddle-fouling" intrusions like thermo-pockets and racking pipes.

Fair point
If you can't have a paddle then you need to look at alternatives for oxygenating the wort.
But for us mere mortals with a simple plastic FVs anything other than two minutes agitation with a paddle or a whisk is unnecessary. Some folks on here even say they don't bother aerating the wort at all, and if you are a kit brewer using a majority of your water without boiling direct from the mains tap through a sparkler its probably not needed

 

[Berserker Brewery]

£3.50 mixer paddle and 2 mins on a cordless drill, either after adding starter, or just sprinkle dry yeast on top and never had a fail. If doing a very big braggot or Imp Stout, will do a 2nd time 12 hrs later. (no it doesn't effect the beer)

 

[CD]

I eventually bought a Tetra APS 100 pump for £19. It seems to work fine with the 50 micron s/s air stone, producing a nice gentle flow of fine bubbles – unlike my previous attempt using the workshop air compressor with its regulator turned down low, or so I thought, which nearly blew all the wort out of my fermentor! I turned it down further after just a few seconds, and the resulting beer seems fine.

I shall slide 2 or 3 M12 stainless nuts down the tube to help the airstone sink low enough on my next brew day (in 11 or so weeks), and probably set the timer to run the pump for 6 hours, rest for 4, then on for another 2. That’s the thought for the moment anyhow.

 

[peebee]

You might have seen this:
Oxygen - How to Brew.
And he's talking about sintered stainless steel air-stone. And syringe "HEPA" filters. All driven from a fish aquarium pump. The sort of complete cobblers I started off with. Aquarium pumps have nowhere near the puff to get air out of them stones, a syringe filter is nowhere near big enough for a pump that can provide the puff, and … at this point would you trust anything written in that book? Yet hundreds do!

 

[CD]

[QUOTE="peebee, post: 949080, member: 7632"
Oxygen - How to Brew.
And he's talking about sintered stainless steel air-stone. And syringe "HEPA" filters. All driven from a fish aquarium pump. The sort of complete cobblers I started off with. Aquarium pumps have nowhere near the puff to get air out of them stones, a syringe filter is nowhere near big enough for a pump that can provide the puff, and … at this point would you trust anything written in that book? Yet hundreds do!
[/QUOTE]

The pump I have just got certainly does have enough puff, though I don’t bother with a filter. I adopted the procedure after noticing that the Princetown Brewery, where I used to scrounge my yeast from, used a similar system in their original mini brewery behind the Prince of Wales pub.

 

[Edison]

FYI, this is the simple setup I use. Today's Helles got a 60s burst as its fermenting at 10c, but usually 30s is enough.