They were competing against the hosts plus teams from Thetford, Corby, Bramcote and Daventry and three of these were in the top six positions in the league table.
Several Dolphins swimmers were unavailable so the team was not expecting to win this gala.
The Dolphins' first win came in the fourth event, the 9-11 boys freestyle relay when Jack Boulton, Chris Gillyett, Aarron Smith and Bradley Janney all swam a great race.
Aarron Smith then recorded two fine individual wins in the backstroke and butterfly events.
In the 9-11 boys medley relay team race Chris Gillyett Henry Cawte, Aarron Smith and Jack Boulton cruised to victory with a nine-second margin over the second-placed team.
Jack Boulton was unfortunate to dislodge his goggles on the dive in his individual freestyle race and this hampered him at the turn so he had to be content with third place.
The 12/13 boys had three individual wins, a team win and a team second place in their six races.
David Trickett used his aggressive style in the breaststroke to swim to a two-second victory over the Market Harborough boy.
Ben Dalton swam a personal best when he won the backstroke, while James Smith won his freestyle race by over two seconds.
David, Ben and James were joined by Edward Cooke to take maximum points in the freestyle team race.
The girls were dominant when counting the second placings, taking 10 of the 12 in the 50-event gala.
Shaunie Johnson did well to get second in a blanket finish in her backstroke, and then she led the freestyle team with Georgia McKay, Heather Cooke and Amy Evans to second place behind a good Corby team.
Robyn Dand, in the 12/13 age group, gained two seconds in the backstroke and freestyle events.
In the 15-year age group there were second places for Megan Stevenson in the 100m backstroke, Lucy Bower in the 100m breaststroke and then these two joined with Robyn Dand and Harriet Cave to collect five points in the medley relay.
The open swimmers came away with two individual and two team second places.
Katie Knibbs in the backstroke and Peter Trickett also in the backstroke both claimed five points, while in the open girls medley Katie Knibbs, Emily Wright, Robyn Dand and Katie Blades claimed second place.
Megan Stevenson replaced Robyn in the freestyle relay and again they gained a runners-up place.
Other swimmers who made valuable contributions to the team's final total were Jaymie Conran, Chloe Gilmour, William Cawte, Jack Remmington, Craig Booth and Mark SMith.
Final result: 1, Bramcote 219; 2, Market Harborough 194; 3, Trenton Dolphins 187; 4, Thetford 180; 5, Corby 153; 6, Daventry 114.