Who Gives A Fish Forums

I've had my Arothron hispidus Puffer for a while now, got him when he was tiny, just an inch long, and now he's about 6 inches. Still, he's never developed any stripes on his belly - just the white spots on a light grey or olive base colour, which changes depending on his mood. He does have the typical yellow swirl around his gill plate and pectoral fins though.

I've seen a couple of other posts about this online, does anyone know why some don't have stripes? Is it a colour morph, or is it related to where they were caught? Could it even be a sex indicator?

Sounds to me like your puffer's got some unique coloring, possibly a morph. Given how rare it seems to be - I've only seen a couple similar ones online - it might actually be pretty valuable. Since you've had him for a while and he's been doing fine, I wouldn't worry about it too much.

Could be a genetic quirk from inbreeding or maybe even some environmental factor at play, depending on the puffer's origin.