Undoubtedly, fish make popular pets while being great stress busters at the same time. A koi fish aquarium full of colorful koi swimming gracefully is enough to mesmerize anyone. If you have a passion for taking care of fish then you may be thinking of buying a koi fish aquarium. The wide range and colorful patterns that these fish sport can brighten up any home. However, there are some important things to consider prior to purchasing a koi aquarium.