Germany won the women's under-21 title for the fourth time in a row at the Canoe Polo World Championships in Welland in Canada.
It came as Britain defended the men's under-21 title which they won at the last edition in 2016.
The German success means they have kept up their record of winning all of the women's under-21 gold medals since the age group tournament was introduced.
They beat Poland 5-1 in a repeat of the 2016 final to maintain their perfect form.
"It was our last year with the team, so we definitely wanted to win the gold," player Esra Ozbay said.
"This is what we have worked for all year.
"We have a great team spirit, we're virtually sisters.
"We have such a strong club competition in Germany, and that really pushes us."
Britain beat Germany's men 3-2 in a hard-fought final.
"There was a lot of pressure on us," said captain Jack Playford, a survivor of the 2016 squad.
"We had a mentality of taking one game at a time.
"We said before the Championships we had ten boxes to tick, each one being a game, tick each one as we go and don't get ahead of ourselves.
"It seems to have worked."
The senior competitions will resume tomorrow.