Aeration Pump Questions

I've found some very scientific discussions of aeration at HBT, although most seem to prefer a stir plate. No doubt, if the graphs are to be believed, a stirplate is much more effective. I was wondering, however, how much benefit a small aquarium pump would do for the starter. I've seen data suggesting a small increase in yeast counts. Does this imply the use of a diffusion stone (2 microns for air)? Am I correct to infer from some posts that, without a diffusion stone, the aerating benefit of a small pump is negligible?

A second question here: most people assert that it is necessary to buy a "sanitary filter." Can such a filter be replaced by bubbling the air through Star San -- much like a three piece air lock in reverse. (And I know that's not what an airlock does.) The air could be forced through the star san solution before entering the starter? I'd been imaging a yeast vial (a White Labs vial perhaps) filled with star san; the air pushed into the solution through a narrow plastic tube; then out the top from a tube flush to the lid. I'm assuming this isn't going to provide enough "sanitation." Although if my starter is covered by a tin foil lid, I'm not quite sure why not. Wouldn't it work as well as a goose neck flask to impede bacteria and particles?

And, to reiterate, the purpose is not to replace the stir plate, but to utilize a very cheap resource. I did try to google this question, here and elsewhere. Thanks in advance.

Luke

I tried the aquarium pump, and filters and all that jazz and never really got the results I was looking for. I finally decided to try pure O2 and have not gone back. A regulator/diffuser wand/tubing kit can be had from a number of online stores for less than $50. I got one for Christmas (love my wife) this past year. I went to the hardware store and dropped a whopping $7 on a disposable O2 welding/brazing cylinder. I just aerated my 10th batch since making the purchase and my cylinder is still pumping out the O2. I even use it to aerate my starters.

I am all about economy brewing. But the O2 setup is a piece of equipment that, when averaged over the number of batches it will serve, in the long run adds next to nothing to the overall cost of your final product.

And by the way, I aerate my starters and use a stir plate. I am sure somebody with a science background will come along and blow my theory out of the water. But I aerate so that even the smaller number of yeast in the starter vial can get a head start on the respiration phase by hitting an oxygen rich environment when I pitch. Then the stirplate provides some additional aeration while also keeping the yeast in suspension and close to their food source.