"Two opalescent koi fish swim in a nebula of swirling stardust and ethereal, bioluminescent light. Their tails elegantly intertwine to form ...

"Two opalescent koi fish swim in a nebula of swirling stardust and ethereal, bioluminescent light. Their tails elegantly intertwine to form the Pisces symbol. Tiny constellations (specifically recognizable Pisces constellation) dot the deep space background. Intricate scales detail, dreamy atmosphere, celestial, watercolor-like shading."

Rationale: This prompt emphasizes the duality of Pisces with the two fish and anchors it in the cosmos, referencing the Pisces constellation directly. The refinement adds a more delicate and shimmering feel with "opalescent" and "bioluminescent", and pushes the aesthetic towards a dreamy watercolor style.