Fomo: Rae Sremmurd's Slim Junkie leaps in Torrens, survives

Before Sunday's festival, attended by about 10,000 on the riverbank, SA Police issued a warning to festival-goers that the council had deemed the water in the Torrens to be unsafe because of the blue-green algae for any human contact.

They also said laws did not permit swimming, including inflatable toys.

But that did not stop Slim Jxmmi, real name Aakil Brown, from taking a dip in the river.

In a video posted on Instagram to his 1.3 million followers, Jxmmi is jumping into the water and swimming out to the nearby paddle boats.

"They asked me what SremmLife was so I jumped in the lake (Adelaide)," he captioned the video

An Adelaide City Council spokeswoman said the council will not be taking action against him.

"We do, however, strongly discourage people from swimming in the river given the quality and safety issues which are a potential health and safety risk," she said.

"It is also an offense under the City of Adelaide by-laws and individuals run the risk of being expiated or prosecuted.

"We certainly encourage people to get out on the water but do so by using Popeye, paddle boats or BBQ buoys."

In a later post to his Instagram story, Jxmmi said he did not realize the potential health issues.

"I just found out the lake was toxic Crazy, "he posted.

"If something happens to the lake did it."

Just days ago Jxmmi was involved in a street brawl in New Zealand.

Rae Sremmurd, Jxmmi and brother Swae Lee, are the best-known for their single Black Beatles which featured in the viral "mannequin challenge" craze in 2016.