Gorgol XIII
From Tardis Wiki, the free Doctor Who reference
Gorgol XIII is a planet home to a mermaid-like race that are able to suck their food through their nostrils, albeit with great discomfort. (K9TV: Liberation)
As the Mermaid-like Merons appeared in the same episode as the Mermaid people of this world was mentioned. It is possible that Gorgol XIII is the Meron homeworld.