Cardiomyopathy refers to the cardiac remodeling process in response to a variety of intrinsic and extrinsic stimuli that stress the heart. To discover novel therapeutic strategies for the disease, we are establishing and characterizing adult zebrafish models of cardiomyopathy. One of the models is tr265/tr265, a line that becomes anemic due to a mutation that ablates erythroid-specific Band 3 protein. Although Band 3 does not express in the heart, the chronic anemic stress induces profound cardiac enlargement and cardiomyopathy-like pathogenesis. Phenylhydrazine hydrochloride (PHZ)-induced anemia model has been established which enables application of anemia stress to any adult fish. In this chapter, we provide detailed information on generation of two anemic models in zebrafish; measurement of the anemia level; determination of enlarged hearts in either organ level or cellular level; and detection of cardiomyocyte hyperplasia, as well as survival rate recording. The protocols described here can be applied to other adult zebrafish models of cardiomyopathy.