Use half RO water and half tap water. Treatw ith 0.5 tsp calcium chloride prior to mash and adjust sparge water pH with phosphoric acid. “I use a Hockhurz-style double decoction for this one and adjust color if necessary near end of boil with pre-steeped debittered black, or Sinimar®.” Mash schedule include a protein rest at 130° F (54° C) for 20 minutes, a maltose rest at 143° F (62° C) for 60 minutes, a dextrin rest at 154° F (68° C) for 40 minutes and a mash-out at 168° F (76° C) for 20 minutes. “Aim for 25ish IBUs. Raise to 60° F (16° C) when it slows, hold for a few days before lowering. Rack to keg and lager about 6 weeks.”