Sorry guys, I asked that already but no matter where I search I cannot find it again!
So, I still did not build that brewer, BUT he promised me for my birthday which was only a month ago IF I find the right pump.
My plan is to use one of these blue barrels which I already have (people use them for rain barrels or aquaponic setups). Now I have to find the right pump for it, someone recommended these pumps: http://www.theaquariumshop.com.au/shopdisplayproducts.asp?id=97&cat=Hailea%20air%20pump Is there a design which is better than the other? Are there designs which are not good?