Yes, you should read about car models before buying a car. You research before you buy a car in order to learn about them and make a decision on which car to buy based on it's price, reliability, longevity, etc...
After that, you get to buy and enjoy the car.
Same deal in fishkeeping. You research the fish first, learn about the science behind keeping a tank clean, the behavior and care of the fish, and all the other necessary elements behind successfully having a fish tank. Then, you get to buy the fish, decorate the tank, show it off, and enjoy all your artistic freedom.
To say that Ichthyology does not deal with real science is simply foolish. Studying fish and their behavior, habitats, and all other apects of their life isn't science? What is then? Are no kinds of zoology scientific? What about anthropology, sociology, psychology, any other kinds of science dealing with humans? They're just the study of a certain type of animal (yes, humans are animals), how is Ichthyology any different?
You really need to quit arguing for the sake of arguing and try to think logically for once.