dye

[cosmo]

has any of your tails have dye come out of it it happened to me and my cousins tails but they still look the same colour

[Spindrift]

Hmm I think that's why you're supposed to wash all fabrics before using it for sewing projects and the like.

[Winged Mermaid]

That's true. First thing you learn in sewing class is to launder the fabric like you're going to launder the garment once it's done, sans fabric softener.
It's nothing to worry about, just give them a good soak or rinse before going in the pool next time.