They did not want to be named.
"We were watching them going out, they were inexperienced people, and the lake is not as calm as it looks. You get out there and it's bigger than it looks.
"We were watching them, they fell off and we thought we had better do something. The conditions caught them by surprise," one of the rescuers said.
The pair were staying in a homestay by the lake.
Homestay owner Ruth Hedemann said the duo were never in any real danger.
"They were both wearing life jackets and they had somebody rescue them straight away, they are just a bit cold," she said.
Karel and Natalija were in Rotorua for three days before they travelled to Auckland.
They had enjoyed their stay, Karel said.
"We have been doing lots of sightseeing. We don't have mountains and stuff in Estonia.
"We will be kayaking again soon. I heard New Zealand was the adrenaline capital of the world. We are heading north to Auckland to do a bungy jump," he said.