On the season premiere of ABC's "Shark Tank," two sharks got heated. And all wet.

"Shark Tank" guest judge and Virgin billionaire, Richard Branson, let regular judge and fellow billionaire Mark Cuban know, in no uncertain terms, that Cuban had rankled his nerves. In the middle of an investor's pitch, Branson dumped a glass of water over Cuban's head. Cuban then returned the favor.

"I playfully threw a little water over him, thinking he was giving me the go signal to do so," Branson writes on his blog about Cuban. "But he wasn't at all impressed with the impromptu shower, so threw some water right back at me."

Branson says the pair made up backstage, but if Cuban forgave, perhaps he didn't forget.

"I don't want to be in the same room with that guy for the rest of my life," he told Entertainment Tonight about the Branson incident recently. "I wasn't happy with him."

Ironically, the fight broke out during a pitch for a product that is supposed to help people calm down, meditation app Simple Habit.

Simple Habit tweet

The disagreement stemmed from Cuban calling Simple Habit CEO Yunha Kim a "gold digger."

Before coming on the show to ask for $600,000 for a 5 percent stake from the sharks, Kim's company had previously raised $2.8 million from other investors. The hefty backing prompted Cuban's "gold digger" comment, which he says is a term the sharks use to describe an entrepreneur who comes on "Shark Tank" as a way to get exposure for their brand, even when they don't really need to raise capital.

Cuban tweet 2

"That is why I called you a gold digger," Cuban explains to Kim on the show. "It wasn't a personal issue, it was more about coming here, not really wanting a deal, but looking to get the commercial."

On his blog, Branson writes that he found the comment "rather offensive."

"I didn't realize the word 'gold digger' was used on the show to mean someone who doesn't need the investment money but comes on Shark Tank for the free publicity," he writes. "I tried to fight for [Kim's] honour, and Mark called me out for not understanding the show." While both Branson and judge Robert Herjavec made offers, Kim left without accepting a deal.

Fellow judge Kevin O'Leary, who wasn't on the season premiere, wanted to be sure that the chair Branson was sitting in (usually his) wouldn't be damp.

O'Leary tweet

Judge Lori Greiner weighed in as well.

Greiner tweet

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