Oxygen aeration with tank

Need advice on pressure setting and SS aeration stone size. Have the oxygen tank and regulator from my gas welding set up. What pressure setting do most of you use with an adjustable regulator. Think increasing the pressure until I see bubbles and backing off a bit will work. A ballpark initial starting pressure setting will help.

Air stone size. Commonly see .5 and 2 micron SS aeration stones. Thinking the .5 would be best as the smaller bubbles should get absorbed quicker.

Is the Williams air wand worth it? Thinking the stone at the end of vinyl tubing may float when oxygen is introduced. The Williams wand gets good reviews, just wondering if the stone and tubing works as well?

I do not use pure oxygen, but your questioned reminded me of something I read about in a book written by White and Zainasheff, YEAST: Practical Guide to Beer Fermentation.
On page 79 they go on to say :

White Labs ran an experiment injecting pure oxygen into 5.3 gallons of 1.077 wort using a 0.5 micron stainless steel sintered stone at a flow rate of 1 liter per minute. The results show that to reach the desired 8 to 10 ppm, you would need to inject oxygen for one minute (9.20 ppm).
Hope that helps.

I like the wand, it seems easy to keep clean. I forget the pressure, I am basically looking for bubbles without having the hose pop off the wand. Keep in mind that any bubbles that reach thet surface are probably waste, so look at the amount at the bottom and the amount at the top as well.

Imperial Stout said:

Think increasing the pressure until I see bubbles and backing off a bit will work.

Air stone size. Commonly see .5 and 2 micron SS aeration stones. Thinking the .5 would be best as the smaller bubbles should get absorbed quicker.

Click to expand...

If the bubbles are flying to the top, they're wasted.  Back it down until you can barely see them hitting the top surface. 

With O2, you MUST get the 0.5 micron stone.  The oxygen molecule is just over 0.5 micron, so that size provides some back pressure and slows the flow.  The 2.0 stone lets O2 fly out much too fast and you'll burn through cans of 02 much too quickly.  Friends here did that and wasted a lot of cash on cans of oxygen.  The 2.0 micron is for the aquarium pumps. 

The wand is cool.  You can also take some copper wire and make a long spiral thing around a dowel and then wrap it around your tubing as a stiffener. 

I used to use a stone, but I've had more success pitching the yeast and shaking the heck out of the 6.5 gallon carboy fermenter. I also use a conical for 10+ gallon batches and basically do the same thing. Fifty shakes is all it takes!

I use a stone with a wand that's attached to an aquarium pump with a filter in between.  Tried disposable O2 bottles, but super expensive.  This method was inexpensive and is super easy.  Sanitize and go.

MaltLicker said:

Imperial Stout said:

Think increasing the pressure until I see bubbles and backing off a bit will work.

Air stone size. Commonly see .5 and 2 micron SS aeration stones. Thinking the .5 would be best as the smaller bubbles should get absorbed quicker.

Click to expand...

If the bubbles are flying to the top, they're wasted.  Back it down until you can barely see them hitting the top surface. 

With O2, you MUST get the 0.5 micron stone.  The oxygen molecule is just over 0.5 micron, so that size provides some back pressure and slows the flow.  The 2.0 stone lets O2 fly out much too fast and you'll burn through cans of 02 much too quickly.  Friends here did that and wasted a lot of cash on cans of oxygen.  The 2.0 micron is for the aquarium pumps. 

The wand is cool.  You can also take some copper wire and make a long spiral thing around a dowel and then wrap it around your tubing as a stiffener.

Click to expand...

Errr... Not quite. O2 diameter is 0.36 nanometers.  Or about 1500x smaller than 0.5 micron.

It is not about back pressure.  It's just about smaller bubbles.  Smaller bubbles have more surface area, and rise to the surface slower.  So, more o2 will directly dissolve.  Second, the smaller bubbles will create a greater convection current which will allow more wort to churn to the surface.  This churning also allows the wort to absorb o2 from the head space.