"Chasing" by Lin Hue-kuei from his book Drawing Sea & Tropical Fish. It is an interesting choice for the artist to depict five angel fish. Angel fish are a sign of perfect relationship union or fidelity. While the number 5 is a sign of change.
There is a special relationship with fish and therefore aquarium keeping in Chinese culture and also throughout Asia. In Thailand, the Philippines, Indonesia, Japan, China and Taiwan there are well developed industries that support and supply the worldwide demand for ornamental tropical fish and goldfish / koi.