The pool was closed while the man was treated. He was taken to Rotorua Hospital by St John Ambulance in a critical condition. The incident happened about 1.55pm.
"We are very proud of the quick action by our Aquatic Centre team as they probably saved the man's life," Mr Pitkethley said.
"Our pool supervision procedures ensured the man's perilous situation was detected soon after he suffered the seizure, and calm and decisive action by our lifeguards produced a good outcome.
"Our team is well-trained for incidents like this but we always hope the training doesn't need to be tested in a real emergency. We are not sure of the man's condition at this stage but our best wishes go to him and our hopes for a full recovery."
The learners' pool remained closed for about 45 minutes while staff underwent a debriefing.
A visitor to the pool said she was sitting in the indoor spa pool when she saw lifeguards react.
"It looked like the man had had an epileptic fit," she said. "He was in the pool and they got him straight out."
A Rotorua Hospital spokeswoman said the man was admitted and was last night in a serious condition.