Not much is known about Supreme Ocean Palace. It is one of the Four Great Sacred Grounds.
In overall power Supreme Ocean Palace is second only to Absolute Monarch Sanctuary with Fourty seven elders with the strongest Great Elder Mo Chenfeng which is in the 8th level monarch and their pillars, the Seven Venerable Ones that consist of two level 10 and five level 9 monarchs which power and influence is only next to their ruler the Sovereign of the Seas who are in the peak of level 10 monarch.
Background - Back when the Supreme Ocean Palace hadn't settled down, they found a source of great darkness lurking at the coast of the sky profound continent. They decided to make it their mission to keep this darkness in check, and therefore created the most powerful barrier formation known to the sky profound continent. Unknown to the supreme Ocean Palace, the source of great darkness actually came from one of the two most dangerous weapons in the entire primal chaos universe.
Sovereign of the Seas - Ruler
Ji Qianrou - he acts like a girl
Mo Chenfeng - Great Elder