McGregor-Smyth was equally as emphatic in the under-16 age group, where she combined with Mana's Danielle Watson to win the K2 500m and 200m titles. She then produced a storming win in her K1 200m final.
McGregor-Smyth added to her gold medal haul by competing up an age group and filling the fourth seat in a Mana-Hawke's Bay combined under-18 girls K4 crew which won their 500m and 200m finals.
Fisher, who has been Auckland-based since November training under new national coach Rene Olsen, continued to prove she is a serious contender for the Rio Olympics.
She combined with fellow New Zealand High Performance Squad member Caitlyn Ryan for a shock win in the open women's K2 500m final.
They beat fellow Kiwis, Olympic and world champion Lisa Carrington and Jamie Lovett, who were second, and Australian Olympians Jo Brigden-Jones and Naomi Flood, who were third. The Aussies are ranked seventh in the world.
Fisher was also in a K4 500m crew, which finished second to a crew featuring Carrington, and finished fourth in the open women's K1 200m final, 1.68s adrift of Carrington, and chasing home world ranked Australians Alana Nichols and Brigden Jones.
"Lisa still sets the standard but it was amazing to beat her for the first time," Fisher said after the regatta.
"That was a massive win and it's given us a huge amount of confidence. That last five months have been huge and I've never trained so hard in my life but it's really paying off."
The Karamu High School product has been training hard as part of a New Zealand K4 squad, which aims to qualify for Rio. Ryan, Lovett, world 5000m champion Teneale Hatton and Kayla Imrie are also in the squad and all have made massive progress under Olsen.
However Fisher and Ryan's success suggest Fisher's versatility and compatibility with Ryan will make her a certainty for Rio. As has been the case since Fisher took up the sport as a 13-year-old, she excels no matter what crew she is in.
