Suzy and Ted Gregory's comments were made during the funeral service for their 22-year-old son, who died in Lake Te Anau on Saturday.
He and a group of Cromwell friends had been in Te Anau at the weekend, celebrating a birthday.
Early on Saturday, Mr Gregory and two friends rowed in a one-man dinghy to a float plane moored near the jetty area.
The dinghy sank on the return journey.
His two companions survived, but Mr Gregory's body was recovered from the lake later that day.
"Listen to me... This dangerous stuff has got to stop," Mrs Gregory said.
"Ricky loved life and loved taking risks, but this is just too hard.
The Gregorys and several of Ricky's friends and workmates talked about how Ricky was the life and soul of every party, and how he touched so many hearts.
Cars and motorbikes were his passion from an early age and he worked hard to save for new vehicles.
He owned several Holden cars, and they were used to transport his family to the service and to carry his coffin.
A fleet of Holdens delivered his close friends to the church, and the wreath on his coffin was decorated with photos of the many cars and motorbikes he had through the years.
