Elliot comfortably took out the mixed 100m butterfly in 1:05.45, beating Whangarei's Jack Milina and Bream Bay's Rebecca Reade by four and eight seconds respectively.
He then kept Mt Eden's John Ashcroft at bay to win the mixed 200m freestyle before winning the 50m butterfly over Willy and Northwave's Ciara Smith.
Whittam was also in form as she grabbed a pair of first placings.
She romped home to a 25s victory in the day's opening event, the 400m freestyle, before repeating the positioning in the 100m breaststroke.
Northwave's Nellie Clark (1:26.74) and Jackson Somner-Allen of Bream Bay (1:26.90) battled for the other podium finishes.
Willy was a shining light for the home club as he picked up three first placings for himself.
After pipping Elliot in the 50m freestyle, he held off Northwave's Annabell Simpson (30.78) to win the 50m backstroke in 30.56.
Willy also won the 100m freestyle, beating Elliot and Smith to the finish.
The final event of the day was a two-horse race between Simpson and Milina as they looked to take the 200m butterfly spoils.
Simpson held a two second buffer at the 100m mark and despite Milina's best efforts, he could not haul his opponent in.
Dargaville Swimming Club will put their hosting hat on next week as they welcome swimmers for the Northland Age Group Championships on February 19.
Results:
Event 1: Mixed 400m freestyle
1) Madeline Whittam (Northwave) – 5:06.19
2) Trinity Greig (United) – 5:31.31
3) Harvey Williams (Bay of Islands) – 5:32.06
Event 2: Mixed 50m freestyle
1) Conor Willy (Dargaville) – 25.94
2) Jeremy Elliot (Northwave) – 26.06
3) John Ashcroft (Mt Eden) – 26.73
Event 3: Mixed 100m butterfly
1) Jeremy Elliot (Northwave) – 1:05.45
2) Jack Milina (Whangarei) – 1:09.60
3) Rebecca Reade (Bream Bay) – 1:13.71
Event 4: Mixed 100m backstroke
1) Quin Walden (Northwave) – 2:40.73
2) Drew White (Bay of Islands) – 2:45.44
3) Emilia Finer (Bay of Islands) – 2:46.09
Event 5: Mixed 100m breaststroke
1) Madeline Whittam (Northwave) – 1:21.16
2) Nellie Clark (Northwave) – 1:26.74
3) Jackson Somner-Allen (Bream Bay) – 1:26:90
Event 6: Mixed 50m backstroke
1) Conor Willy (Dargaville) – 30.56
2) Annabell Simpson (Northwave) – 30.78
3) Anna Lepua (Tbss Central City) – 34.75
Event 7: Mixed 200m freestyle
1) Jeremy Elliot (Northwave) – 2:10.50
2) John Ashcroft (Mt Eden) – 2:11.74
3) Archie White (Bay of Islands) – 2:17.61
Event 8: Mixed under 12 4x50m freestyle relay
1) Bream Bay – 2:11.87
2) Bay of Islands – 2:20:63
3) Dargaville A – 2:20.77
Event 9: Mixed 13 and over 4x50m freestyle relay
1) Bay of Islands – 1:58.93
2) Bream Bay A – 2:00.96
3) Bream Bay B – 2:10.43
Event 10: Mixed 400m individual medley
1) Annabell Simpson (Northwave) – 5:23.75
2) Rebecca Reade (Bream Bay) – 5:51.65
3) Janaye Burns (Pukekohe) – 6:03.75
Event 11: Mixed 200m breaststroke
1) John Ashcroft (Mt Eden) – 2:49.06
2) Emilia Finer (Bay of Islands) – 3:03.28
3) Luka Clark (Northwave) – 3:05.91
Event 12: Mixed 50m butterfly
1) Jeremy Elliot (Northwave) – 27.06
2) Conor Willy (Dargaville) – 28.34
3) Ciara Smith (Northwave) – 32.11
Event 13: Mixed 200m individual medley
1) Jack Milina (Whangarei) – 2:39.28
2) Madeline Whittam (Northwave) – 2:39.78
3) Katelin Milina (Whangarei) – 2:50.03
Event 14: Mixed 100m backstroke
1) Archie White (Bay of Islands) – 1:12.30
2) Ciara Smith (Northwave) – 1:16.37
3) Anna Lepua (Tbss Central City) – 1:17.25
Event 15: Mixed 50m breaststroke
1) John Ashcroft (Mt Eden) – 34.13
2) Jackson Somner-Allen (Bream Bay) – 37.63
3) Luka Clark (Northwave) – 39.87
Event 16: Mixed 100m freestyle
1) Conor Willy (Dargaville) – 58.21
2) Jeremy Elliot (Northwave) – 58.66
3) Ciara Smith (Northwave) – 1:04.88
Event 17: Mixed 200m butterfly
1) Annabell Simpson (Northwave) – 2:37.21
2) Jack Milina (Whangarei) – 2:40.03
