I have the opportunity to pick up an 18" Piraya but it is 12+ years old. On one hand I would like to grow out a 12" but it does have the chance to only get to 14" or something. And that's fine too but I would like a nice big fish. I was wondering on average and in your guys' experience, how long do Piraya's live? I've heard 20+. Is this true? I was also wondering if they get sluggish when they are 20+? Right now the 18" doesn't look sluggish at all. Looks great actually. I have no problem keeping a fish for 20+ years also. That's fine to me.