I bought mine as a 3" juve back in June 2016. He is a good 10" now and quite thick with it. Yours looks slimmer and more streamlined than mine and also the tail on yours is a proper fork. The tail on mine, the bottom lobe is larger and more rounded than the top lobe, you can make it out in the picture though the angle isn't brilliant.
Mine grew up in a 180 and at times would throw some right wobbles. They are insanely fast, i'm surprised he never injured himself. Then when I put him in his current 360 he calmed right down immediately. No more spurts of mad speed when spooked, he's proper chilled now.
I'll be honest with you, I don't even know which chalceus he is. I bought him as a pink tail but if yours is a true pink tail I don't think mine is.
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