Does anyone know the name of these mermaid collectibles?

It was these mermaids fully out of plastic and not like Barbie or Disney and they would change their hair, top and tail color when you put them in warm water. I had a whole collection but distinctly remember two of them (i drew them from memory). I bought them at a shop named Neitzel in my small hometown between 2014-2018 (i think). Does anyone else remember them or perhaps even their name?