Mr Weisswange went missing during a kayaking trip on Lake Hawea on August 29 and has not been found.
His borrowed kayak and broken paddle were found washed up on the shore beneath the village on August 31.
A tearful and sombre memorial service to lift a tapu on the lake was attended by his parents, Birgit and Volker Weisswange, and many of the LandSAR volunteers who have been searching the lake and shoreline for the missing man.
Rene Weisswange had lived in the village for about two months.
In an emotional speech in German, which an interpreter translated, Volker Weisswange said his son meant everything to his family and would always be in their memories.
"Every moment with you was so precious, so fascinating and unique. You were a very loving and extraordinary person, a good son, brother and friend ...
You were everything to us and we will miss you forever," Mr Weisswange said.
Jeromy van Riel, Brent Pihama and Justin Hawea led a stirring whaka noa, a Maori ceremony, to lift a tapu placed on the lake on Sunday.
Mr van Riel said the tapu was placed when he was asked by the Lake Hawea community to be part of the ceremony.
"The rain this morning and the southwesterly wind has come in, I believe not by chance to give us the cleansing water and winds to clear this area. We are going to use that strength and intention to return our lake to a state of harmony and tranquillity," Mr van Riel told media before the ceremony.
The blessing had been confirmed by iwi representatives from Southland and Otago, who had sent their love and condolences, he said.
During the ceremony, Mr van Riel said he had learned Mr Weisswange had an adventurous, mischievous and cheeky nature.
"When our ancestors called him, he had no choice but to go to them," he said.
Michelle Cotter, on behalf of Lake Hawea residents, welcomed Mr and Mrs Weisswange, expressed sorrow and offered comfort.
She encouraged people to sprinkle rosemary for remembrance and daffodils for renewal on the lake, before leaving the area in peace.
