Little Huia resident Ken Turner was the skipper of the boat which spotted the stricken men.
Mr Turner, 57, had four people - including his son Adam Turner, 24, and niece Louise Pieters, 24 - on board his 5.5m boat when they saw the red life jacket of the first survivor. "He started waving at us," Ms Pieters said.
When they reached him, he told the group he had been with four other men, and one had already died. "We managed to drag him on board. He was exhausted," Adam turner said.
The group - which included Ms Pieters' boyfriend Devon Booth, 25, and friend Tessa Leake, 23 - called police and began to look for the other men.
As they headed closer to the bar, where the men had drifted, conditions on the water worsened.
Terangi "Toots" Woonton was killed in the boat tragedy. Photo / Supplied
"When we got to the second person ... he was really shattered and had really bad cramp," Ms Pieters said.
Adam Turner added: "It was a 3m swell."
The next man they found had already died, and a decision was made to leave him and continue searching. "The fourth person was the third survivor. He was much bigger and older," Mr Booth said.
"He was quite hard to get into the boat. We put him in the recovery position, we were quite worried about him."
The fifth person they located was unresponsive, Ms Pieters said. Mr Booth and Adam Turner hauled him into the boat, and then began compressions.
"Adam started driving and I was confirming with police because we weren't sure what to do," Ms Pieters said. "We still needed to pick up [the other guy], and that's when we decided we needed to offload those other guys who were well enough."
Watch: Two killed in boating tragedy
They headed to Paratutai Island, where the three survivors jumped out of the boat and were looked after by a fisherman and his wife.
The group then located the final man, who was also unresponsive, with the help of the Westpac Rescue helicopter hovering over his location.
"You don't think about your emotions, you just think about trying to find the next person," Adam Turner said of the rescue.
The group, who were sightseeing around the harbour, said it was lucky they had spotted the first man because no other boats were around.
"You don't really notice how rough it is because you're focusing on finding the next person," Ms Pieters said. "You just get tunnel vision."