Prime's medal haul in Wellington was nearly half of the Northland team's total, with the group winning a remarkable 20 national medals between them.
Bay of Islands' Daniel Gaualofa, swimming in the Athlete with a Disability category, also picked up where he left off last season - winning six national medals.
Gaualofa, fresh from making his senior team debut for New Zealand at the Para Pan Pacific Championships in California, won gold in the 100m breaststroke and silvers in the 100m backstroke and the 400m freestyle.
He also brought home bronze medals in the 50m freestyle, the 100m butterfly and the 200 individual medley.
Other Northlanders to secure national medals were the Northwave trio of Ciara Smith, Ellie Eastwood, and Hayley McIntosh.
Smith won all her medals in the breaststroke events, securing silver in the 13 years 200m breaststroke and bronze medals in the 50m and 100m events.
Eastwood won bronze in the 14 years 200m breaststroke event, and also placed ninth in both the 200m and 400m individual medleys and 10th in the 100m breaststroke.
McIntosh secured her bronze in the 15 years 200m backstroke, and also placed fifth in the 200m and 400m freestyle, seventh in the 100m backstroke and eighth in the 800m freestyle.
McIntosh and Smith were both selected to attend the New Zealand Age Group Development Camp, where they will join Prime, Eastwood, Matthew Gordon and Madeline Gordon - who were all selected following the national Age Group (Long Course) Championships earlier this year.
The other Northlanders to compete in the champs were Bream Bay's Ruby Lee Beckham, 16, and Rose Linton, 13.
Northland's top 10 finishers:
Callum Prime (Northwave), 14 years: 1st: 100m backstroke; 1st: 200m backstroke; 1st: 400m individual medley; 2nd: 50m backstroke; 2nd: 100m freestyle; 2nd: 200m freestyle; 2nd: 200m individual medley; 3rd: 100m individual medley; 3rd: 400m freestyle.
Daniel Gaualofa (Bay of Islands): 1st: 100m breaststroke; 2nd: 100m backstroke; 2nd: 400m freestyle; 3rd: 50m freestyle; 3rd: 100m butterfly; 3rd: 200 individual medley.
Ciara Smith (Northwave), 13 years: 2nd: 200m breaststroke; 3rd: 50m breaststroke; 3rd: 100m breaststroke.
Ellie Eastwood (Northwave), 14 years: 3rd: 200m breaststroke; 9th: 200m individual medley; 9th: 400m individual medley' 10th: 100m breaststroke.
Hayley McIntosh (Northwave), 15 years: 3rd: 200m backstroke; 5th: 200m freestyle; 5th: 400m freestyle; 7th: 100m backstroke; 8th: 800m freestyle.
Paul Linton (Bream Bay), 13 years: 4th: 50m backstroke; 4th: 100m backstroke; 7th: 200m backstroke.
Jeremy Elliott (Bay of Islands), 13 years: 4th: 200m butterfly; 5th: 400m freestyle; 5th: 100m butterfly; 9th: 200m individual medley.
Kieran Swords (Bream Bay), 15 years: 4th: 50m butterfly; 6th: 100m butterfly; 8th: 50m freestyle; 10th: 100m freestyle.
Annabell Simpson (Northwave), 13 years: 5th: 200m backstroke; 7th: 100m backstroke; 7th: 400m freestyle.
David Van der Star (Northwave), 18 years: 9th: 50m butterfly; 9th: 200m freestyle.
Dylan Sims (Bream Bay), 16 years: 7th: 50m backstroke; 9th: 100m backstroke; 10th: 200m backstroke.
David Clarke (Bay of Islands), 16 years: 9th: 50m freestyle.
