I am about to construct my first HERMS
I was reading this:
You probably have a small beverage cooler already that would work well with a drop-in manifold like that shown with the rectangular cooler in Appendix D. One advantage to using a manifold, versus pouring the mash into a strainer, is that you avoid aerating the wort while it is hot. As was discussed in Chapter 6 - Yeast, and Chapter 8 - Fermentation, oxidation of hot wort at any time will lead to flavor stability problems in the beer later.
Source: PALMER - how to brew: http://www.howtobrew.com/section3/chapter18-3.html
I imagine that by circulating the mash, more of the liquid would come in contact with the air. I was wondering what kind of inlet manifold for the returning hot mash I would use to minimize oxidation.