The studies involve mixing sodium, calcium, potassium, and chloride to find which combinations help fish grow as large and fast as possible. Results suggest that adding sodium chloride improves the growth rate of juvenile redfish in fresh and brackish waters. This could be important when these fish are produced at inland aquacultural sites or when saline groundwaters are utilized. Neill and Gatlin are also investigating how oxygen levels affect fish growth. If too little oxygen is present, the fish will have to work harder to obtain the oxygen they need, may not eat as much, and may grow more slowly.
Work is now underway to develop methods to generate optimal oxygen levels in production systems.
A semi-purified diet has also been developed to determine the nutritional needs of young fish. Connie Arnold has developed closed systems for intensive year round production of redfish and shrimp, and is now evaluating low pollution diets for fish grown in these systems. Arnold has also developed methods that simulate temperatures and day lengths to induce spawning in redfish. One of the major problems that's limited the success of Texas aquaculture has been that redfish and tilapia have a hard time surviving cold winter weather. The problem is especially troubling because nearly all Texas' operations are outdoors and many aquacultural enterprises need year-round production and profits to survive.