The fledging group enjoyed surprising success in a series of elections between September 2011 and May 2012, including capturing seats in the Berlin city-state legislature and garnering strong support in the western state of Saarland.
But since a poll last spring put them at 13 percent in terms of voting intentions for next year's federal election, levels of support today have dropped below five percent, the key threshold for entrance into the Bundestag, or lower house of parliament.
Now the party is scrambling to present a cohesive policy platform that will carry it into elections set to held in September or October next year.
"I hope that at the end of this congress we will have a roadmap for our economic policy, foreign policy, energy policy and the fight against corruption," said party head Bernd Schlömer. "These are my minimum goals."
At the start of the conference in the western city of Bochum, he acknowledged to the delegates the "errors" his novice party had made.
"We need to concentrate on what matters... good policy," he said.
But the Pirates' decision making process is agonizingly slow – on the first day of the two day conference the around 1,900 party members only managed to decide upon five of the 800 proposals submitted, despite the party leadership's goal of at least 80 decisions.
On Sunday, the Pirates reconvened to discuss whether to set up a constant rolling conference online as a new party organ to close the gaps in their programme.
The German Pirate Party was founded in 2006 following the model set by a Swedish group. It is populated mainly by younger people and its platform has focused on internet freedom and digital empowerment.
It was only last year that they gathered a critical mass of support, but that surge appears to have petered out.
Most Germans today don't take the group seriously and what was initially welcomed by some as an anti-establishment novelty has now lost some of its appeal after a string of random policy statements and party in-fighting.
In one incident, which perhaps reinforced some of the party's negative caricatures, the group's political director Johannes Ponader appeared on a television talk show in sandals and a scruffy jumper.
Between ostentatiously checking his mobile phone he spoke about how he lived on state handouts.
"We made some mistakes," Ponader said on Saturday. "We made public some conflicts that belonged in the personal realm, but we've fixed that."