I've found that a fish year on this game is about 5 mins. long when you're in 2X speed.
And a fish pregnany takes 4 fish years to complete.
So a fish pregnancy goes on for about 20 mins. in 2X speed, which is 40 mins. in normal time, and 1hr and 20 mins. in 1/2 speed.
And a fish year would be 10 mins. normal time and 20 mins. 1/2 speed.
I hope you found this helpful!

Very useful information. Thanks.

Paul

You're welcome. I'm glad somebody finally replied

Thanks to your useful infos...

Cheers.

Glad to help!

Thanks!

plus, the oldest you can view a fish is 20 yrs--so that's 100 minutes.

If I understand the post correctly... you do see the species of fish once they reach the age of 20.
If you are referring to the age it lives to, fish don't die of old age, so technically, they can live for over 1000 years.... unless of course they get sick or you don't feed them!