Covering the carboy when aerating?

[bryangm]

I'm about to try an aquarium pump/diffusion stone this weekend to aerate my wort. I know I should probably let it aerate for 30 minutes, but during that time should I be worried about contamination with the carboy mouth being left open? I'd imagine that it's probably not good to use a rubber stopper if I'm pumping air into the carboy, but does anyone have any other techniques they've used to reduce the risk contamination?

 

[BradleyBrew]

Sanitized foil. Same most people use for starters. Works perfect. Be ready for a lot of foam

 

[wolfman_48442]

I don't think you have anything to worry about, but I've had moments of paranoia myself.
I've used a sheet of paper towel moistened with starsan over the lid of a keg I was transferring to. I suppose it worked fine - nothing bad happened, and I felt better

 

[bryangm]

Thanks for the tips, I believe I'll give the foil a try...just to make myself feel better

 

[Stauffbier]

I use foil as well.

 

[zendog]

You are creating positive pressure in the carboy. Unless you're concerned about a critter flying in, don't worry about it.