The owner of this cat is being cruel to fish
The video maker and probably the owner was entirely wrong to allow this silver tabby cat to entertain himself by grabbing captive fish in a small aquarium. We know that fish feel pain. I'd argue that they probably feel some basic emotions at the least. The experience is going to be terrifying for the fish. And to make a video out of this is not clever. It is just bad and insensitive. It another example of animal abuse to make an interesting video. It is remarkable how often it happens. It is as if some people equate animal abuse with good videos. No moral compass. Cheap, quick thrills at the expense of animals. I am told that the video was made in Indonesia. Surprise, surprise. They are not known for their animal welfare.
I am unsure if the cat in the still image is the same as the cat in the video. It doesn't really matter. This was cruel behavior by the human. You can't blame the cat as he is behaving instinctively.
Note: This is a video from another website. Sometimes they are deleted at source which stops them working on this site. If that has happened, I apologise but I have no control over it.