I think "heat stress" is referring to keeping cool water available for the D-lineman during practice when it is 95 degrees out, NOT heat stressing during a mash-out. Either is fine, just don't shock it with boiling water to preheat.
I don't think you can buy a "chemical leaching" cooler at any price, but that is just my opinion, stainless perhaps?
Originally Posted by runningweird
if you are concerned about the plastics in coolers leeching chemicals(which I think that they do) then you must abandon the cooler route and go with a metal mash tun.
Facts or opinion?