A "mates' good day out" on Lake Rotorua quickly turned to tragedy for five friends after their boat capsized.
Today, his fishing friends said they had little time to try and save him before he quickly disappeared under the choppy surface.
No lifejackets were onboard the boat as it took in water and capsized around 500m offshore from Ngongotaha.
One of the men said the group, all in their mid-20s, had decided to go out fishing late in the afternoon after checking the "glassy" lake conditions.
"We thought it was so calm, so why not go out. We launched near my parents' house and mucked around in the inlet before we decided it was safe enough to go out into the lake.
Two of the men stayed with the overturned hull while Mr Rouppe van der Voort and two others swam towards the shore, using emptied gas tanks from the boat for flotation.
As they were swimming one of the men looked back to see Mr Rouppe van der Voort struggling.
"He had gone quiet, I looked back and saw his face turn grey and then blank, then saw him go under.
"I don't think even if we were all around him we would have been able to save him, he sunk so quickly."
A boatie on shore heard their cries for help and launched his boat to rescue the four men.
Coastguard spent several hours on the lake last night searching unsuccessfully for Mr Rouppe van der Voort.
His mother, Julie, said she believed her youngest son, an epileptic, had a "grand mal" seizure as he was swimming to shore.
Police alerted her last night that her son was missing.
"It's just like the movies, you have someone knocking on the door, but it's for you this time," she said.
She and Mr Rouppe van der Voort's elder brother, Carl, and his dog, Ice, were at the Reeme St boat ramp this morning.
"If he had not had the seizure he would have been able to swim to shore. He would have died peacefully, he would not have heard or seen anything when he had the seizure," she said.
She said her son, an apprentice builder, was a strong swimmer and enjoyed the outdoors.
"He loved creating things and would go out of his way to help his friends, he loved his mates.
"He was on a mates' good day out.
"He was a good guy, confident in the water, he knew his limits.
"He was under medication but he would not have thought he would have a seizure in the water."
Mrs Rouppe van der Voort met up with the four friends late last night.
They had discharged themselves from hospital after being treated for hypothermia.
"When the weather got up the men said they thought they were on the open sea, not a lake," Carl Rouppe van der Voort said.
"It didn't take long, within 20 minutes they were gone with every wave."