After a scoreless first quarter, Germany seized control with three goals before half-time.
Their high press created Irish turnovers and some lapses in concentration allowed them to capitalise on their opportunities.
Elian Mazkour, Malte Hellvig and Marco Miltkau put the game beyond Ireland before the interval.
Miltkau scored again just after half-time and Timm Herzbruch added a fifth goal before the end of the third quarter.
Hellwig’s penalty corner goal was his second of the game and came with eight minutes remaining, but there was still time for Thies PrInz to make it seven.
Tumilty, whose side are bottom of the standings after two wins in 14 matches, added: “We didn’t do ourselves any favours with that performance and they were exceptional in the circle. These teams just capitalise on errors. There have been phases of play, in both games over the past few days, that have been pleasing but we need to have more of those phases.
“The challenge is to learn from it. It’s a tough lesson but sometimes I think you always learn more from defeats than you do from winning.”