I'm working on a Powerpoint presentation on photographing fishing activities.

When photographing fish that are going to be released, in cases where the fish may legally be held out of the water, I try to get my shots in
15 seconds. In some cases I might do another 15 second shot series after resting the fish for a few minutes.

So, my question is, what is a reasonable amount of time to have the fish out of the water.

I'd appreciate some serious answers on this.