Hokay, I made collages of all my favourite colour scheme ideas, so I'd love to get everyone's feedback!
COSMOS TAIL
Inspiration: opals, mother of pearl, galaxies, crystals
Main colours: mostly cool colours - deep blues, soft violet, teals, pastels, accents of electric blue and gold/silver
This was my first idea for the tail, and probably my most ambitious. I wanted to catch all the colours of galaxies and nebulae, with a bit of the stark beauty and harshness of crystal formations, and in the end make a full costume that is a little other-worldly. I know a couple of other mers - off the top of my head Galene, Selene and Aino - have designed space-themed tails, however loosely, so I don't want to step on any toes here! However, I am confident Pearlie could come up with something fantastically unique!
Costume ideas: crystal accents, iridescent fins, pale hair, violet contacts
FAE TAIL
Inspiration: peaches, cherry blossoms, water colours, the sky at dusk
Main colours: pastels! mostly violet & peach, with pink accents & sage green
Pastels aren't usually my thing, but there are some colours I really gravitate towards, especially in this combination; I love the overall look of the delicate violets and rosey pinks, calming greens and soft peaches. For my fae colour scheme, I wanted to lean towards the ethereal and ephemeral.
Costume ideas: wings, pastel hair, decorative blossoms, soft bronze jewellery
CORAL TAIL
Inspiration: pale oceans, coral reefs, seafoam, salmon, overcast skies
Main colours: soft teal, grey-blues, bright coral pink
I really love coral paired with teal. Like, adore it. It feels so mermaidy without being the stereotypical blue or orange (not that there's anything wrong with that

). My ocean/mermaid-themed tumblr is always centred around these colours. I also like that it's a mix of soft & strong colours, so I'd stand out a little more without being over-the-top.
Costume ideas: pearls, coral-inspired jewellery, light fabrics & soft lace accents
L'AUTOMNE TAIL
Inspiration: Mucha, autumn leaves, harvest fruit
Main colours: deep orange, rust, muted reds, creamy peach
I'm an autumn, so this seemed like a natural colour choice

I wanted to pull the oranges away from the Splash tail, so they're deeper and more muted - almost brown. I would maybe throw some grey-green or olive in there, to break it up a bit!
Costume ideas: russet/deep brown hair, autumn leaves/berries, garlands, bronze & gold accents, earthy accessories
LAGOON TAIL
Inspiration: freshwater fish, toadstools, forests, ponds, kelp
Main colours: deep red, burgundy, muted greens, moss, cream
These are the colours that were originally going to go on my tail from Kanti. I love this colour scheme, but it's a little too close to my current tail's colours, I think. Richer and deeper, definitely, but if I'm spending this much money on something, I want it to be significantly different from what I already have. So, I suppose this is only in here because I like looking at it

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