You can use っていうか to correct what you said before.
When used in the middle, it means 'rather than.'
When used at the beginning, it also means 'rather than,' but sometimes it is used as a sign to change the topic.
This sentence is very colloquial, but as a whole, the girl describes raindrops that look like fish.
She seems so impressed by how the raindrops look lively, but she sais they were just raindrops.
To my mind both instances of ていうか brought up in this thread function as approximation. The speaker looks for a good word for something that they want to describe and comes up with one. Still, they are not satisfied with it. This is how ていうか enters the text.