How old is a 1000 lb marlin?

Excuse me, but I'm curious about something I've been pondering. I came across the mention of a 1000 lb marlin, and it got me wondering - how old might such a colossal fish be? Is there a general rule of thumb when it comes to estimating the age of a marlin based on its weight? Or does it vary widely depending on factors like species, environment, and diet? I'm genuinely fascinated by this topic and would appreciate any insights you might have to offer.