That's a tad high for a scomb of that size, but it's not bad. It's quite a bit less than you'd have paid if you got it online with shipping.
Scombs are small and quick maturing for payaras. They're sexually mature adults by six inches and only live for five years or so in the wild (exceptional cases withstanding).
You likely have at least half a decade left with that fish, and he has the ability to live his entire life in a 75. They're not bad fish, just misunderstood. That, combined with shippers bringing in getiatric large adults in stead of healthy young fish, has given them a reputation that they don't deserve.
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