I'm planning on making a walk in cooler to keep sap in until I can boil on the weekends using a coolbot type system. I scored a deal on used cooler panels and I'm going to fab something up this summer for next season.

I currently use 275 gallon IBC totes for storage (about 500 gallons/week).
What would be the best way to cool sap once I put it in the 36* cooler?
Do you think some sort of agitator or circulation pump to mix the sap?
Maybe cut off the tops of the totes to let heat escape?
Or a SS dairy tank.