Rayadurgam's sister Padam and her husband Nagesh Kakanoor spent the morning at the Ganesh Hindu Temple at Papakura in south Auckland.
The 23-year-old student at the Auckland University of Technology, disappeared on Oct 1.
Some of his clothes and personal belongings were found near the Westhaven Marina the next day.
Police searched the harbour near the Marina last week and tomorrow specialist search teams were due to search the inner harbour.
The Kakanoors said they were still hopeful he would be found alive but also preparing for bad news from police that he could be dead.
Mr Kakanoor has been searching near the marina on most days since Mr Rayadurgam disappeared.
The New Zealand Press Association quoted him as saying the family wanted help from anyone who may know what happened to him or had information which would help the search.
Rayadurgam had lived with the Kakanoors since arriving in New Zealand in Feb 2009.