Chinese algae eater (Gyrinocheilus aymonieri ) is a freshwater ornamental fish native to rivers of the Mekong Basin in Southeast Asia. This species is sold in high volumes in the freshwater aquarium industry due to its usefulness in controlling algae growth in home aquariums. Although G. aymonieri have been successfully cultured in farm ponds, challenges associated with larval survival and labor efficiency persist including the inability to grow this species to market size in a recirculating aquaculture system . To gain insight into the larval development of G. aymoneiri , developmental milestones, digestive enzyme ontogeny, and digestive tract morphology were examined. 7800 newly hatched G. aymoneiri were distributed equally among three 10 L tanks and fed a microdiet (MD) twice daily to satiation from two to 30 DPH (days post hatch). Three to five larvae were removed from each tank at each of 17 timepoints throughout the trial, photographed, measured, and assessed for developmental characteristics including eye and mouth formation, swim bladder inflation, and flexion . Larvae were preserved for digestive enzyme analysis and histological processing. The growth of larval G. aymoneiri followed a linear pattern with the notochord length increasing from 4.988 mm at 3 DPH to 8.99 mm at 30 DPH (Fig. 1). Eye pigmentation was seen at 1 DPH, with subsequent mouth formation and the onset of feeding at 2 DPH. Swim bladder inflation occurred soon after mouth opening at 3 DPH and with a single-lobed morphology. Larvae began to undergo flexion at 11 DPH and completed flexion at 19 DPH. At the completion of flexion, the swim bladder of G. aymoneiri became bi-lobed with a larger anterior lobe and a smaller, cylindrical posterior lobe. The activities of digestive enzymes including lipase, trypsin, and pepsin will be assessed at each of these timepoints via standard microplate assays. The changes in digestive tract morphology throughout the larval period will be visualized using histology. Together, these data will provide insight into the digestive capacity of this species throughout the larval period. This information will aid in improving larval diet and culture conditions to optimize growth, survival, and production efficiency.