Cameron van der Burgh upset world record holder Adam Peaty in the men's 50 metres breaststroke and Tatjana Schoenmaker won the 100m breaststroke.
Chad le Clos completed a sweep of butterfly titles at the Gold Coast Commonwealth Games on Monday to cap a three-gold performance for South Africa on a penultimate day of the swimming programme that produced several upsets.
Le Clos' third gold of the meeting was followed by Cameron van der Burgh's upset of world record holder Adam Peaty in the men's 50 metres breaststroke and Tatjana Schoenmaker winning the 100m breaststroke.
Van der Burgh won the sprint breaststroke title for the third successive Games, while Schoenmaker won her second title at the Gold Coast Aquatic Centre after she had earlier won the 200m race.
"Cameron was phenomenal. I have to say that upfront. That was one of the best performances I've ever seen him do," Le Clos said. "Also Tatjana the superstar getting the double gold so I knew I had to win tonight.
"A lot of pressure obviously going in as favourite (and) it was a hard race and I kept my cool in the end."
The powerhouse Australian team had actually started with successive sweeps in the first two finals of the session but the upsets then started to flow.
Van der Burgh's upset of Peaty was not the only surprise on day five at the pool, with Bronte Campbell also swimming down older sister Cate to win the blue riband 100m freestyle.
It was Bronte's first individual gold medal in her second Games. She has won three relay gold medals, two individual silvers and a bronze and has often played second fiddle to Cate.
Wales' Alys Thomas also surprised many when she won the women's 200m butterfly by almost two seconds over Australian duo Laura Taylor and Emma McKeon.
"I'm overwhelmed and over the moon," said the 27-year-old Thomas, who had not swum at a world championships or Olympics until last year in Budapest.
"It means so much. I've been so patient and waiting for such a long time."
Mitch Larkin had earlier pipped Le Clos to a sweep of individual titles when he won the men's 200m backstroke to again lead an Australian one-two-three finish.
The 24-year-old, who also led an Australian sweep in the 50m race, clocked one minute, 56.10 seconds to just beat Brad Woodward, who had led for much of the four laps of the pool, and Josh Beaver.
"People kept saying it had never been done, and I never knew that, which is awesome," Larkin said of his feat of winning all three titles.
"It's amazing to make history, but obviously this medal represents so much, and this week has been so proud for my career, coming back from a hiccup or whatever you want to call it.
"To finally get my groove back means so much more than a gold medal.
Ariarne Titmus then led another Australian sweep as she overpowered the women's 800m freestyle field to finish in 8:20.02 and clinch gold by more than 10 metres over compatriot Jessica Ashwood.
Kiah Melverton produced a storming finish to win bronze.
"After seeing the boys go one-two-three in the backstroke I thought there might be a chance for us, Titmus said.
"I could have gone a bit faster but I guess it was about racing and I'm glad I could be first to touch the wall."
Australia's Matt Levy won the men's S7 50m freestyle, while New Zealand's Sophie Pascoe won her second gold of the Games when she won the women's SB9 100m breaststroke.
Australia have already assured themselves of finishing top of the medal table in the pool with one day of competition remaining. They have a total of 60 medals, 20 of which are gold.
England are second with eight golds in their 20 medals.
