hey Seafever, my guess is that 125 lb fish at the Vancouver Aquarium you saw was a Skilfish (the only other member of the fish family Anoplopomatidae (Sablefish or black cod is the other member)
The Skilfish are the big boys, growing up to about 200 lbs. Not trying to be a know-it-all here, but here's what made me post this: a hundred years ago, fresh out of University with a degree in fisheries, I was on my lips in a bar in Sitka, Alaska one night. I'd just signed on to a black cod commie boat fishing in the Gulf of Alaska and it was our first night "on the town".
So there on the wall of the bar was an old newspaper clipping of a guy holding a 125 lb + "sablefish". The deck boss of the boat I was on, knowing I had a degree in fisheries and wanting to see if he could make me squirm in front of all the other commie fishermen, bet me $ 100 that I didn't know what the fish was in the picture (he was baiting me, assuming I'd just read the newspaper clipping description and say "sablefish".
About the only thing I learned after 4 years of studying fisheries was the two members of the family Anoplopomatidea, and I knew the bigger ones weren't sablefish.... so I win the bet by saying, "hey, everyone knows that's a Skilfish, right?"
The guy was pissed but he paid up, and after buying every one a round, the greenhorn college kid was broke again....
thought I'd throw that in at the risk of hi-jacking the thread....
How big to P. cod get? I worked on a Japanese L/L boat out on the Aleutian Chain (Adak, Attu) where for some reason, P. Cod grow huge--- I've seen then pushing 40 lbs---but it's rare. Normal commie "market" P. cod are 5 to 15 pounds; in shore, where there are the P. cod nurseries, you'll see them at 2 to 4 lbs---those are the best eating ones, but as noted, they can get real wormy, especially if you catch them near sea lion rookeries
The one in the picture below is 30 lbs (caught in Japan on rod and reel)