Shrimp Farm Wastewater Treatment by Biological Methods
During the past ten to twenty years, shrimp farming has became a major income producer for a number of countries in Asia and South America. Shrimp farm wastewater treatment has become a major issue.
In fact, shrimp farming will be one of the top aquaculture industries in the near future. The demand for shrimp for continue to grow and it has become a major export for countries such as Ecuador, Thailand, Vietnam, Indonesia, and Brazil.
Along with this economic growth has come environmental problems. In particular shrimp farm wastewater, a type of agriculture wastewater, is a major concern in shrimp farming. Shrimp farm wastewater causes two main concerns; it affects the quality and quantity of the shrimp and it causes environmental problems in future growing seasons. In the future, shrimp farm wastewater treatment will become important industry for continued growth of shrimp farming.
Shrimp farming problems are generally caused by:
- High Shrimp Density – Shrimp farms typically have 200,000 – 400,000 post larvae shrimp per hectare (about 2.5 acres). With this high of a density of shrimp organic wastes accumulate rapidly. These wastes include; excess food, shrimp waste, and exoskeleton material. These wastes sink to the bottom of the shrimp farm and are generally not further metabolized aerobically. The wastes then are degraded anaerobically forming toxic chemicals such as nitrate, methane, ammonia, and hydrogen sulfide. These chemical cause a variety of problems including an increase in shrimp mortality.
- Overfeeding – As mentioned above, overfeeding causes an excess of organic material in the shrimp farm. The native bacteria are simply overwhelmed and cannot degrade this material fast enough.
- The number of Shrimp Farms in the same area – Too often, there are a number of shrimp farms in the same geographic area. Diseases of shrimp are too easily transmitted from farm to farm.
- Bad Farm Management – The commercial shrimp farm industry has grown very fast. Little though has been given to shrimp farm wastewater management or best practices. Reckless use of chemicals, disinfectants, antibiotics, and pesticides is destroying the ponds natural ability to degrade the organic material.
Ultimately, the question that need to be asked is: “How do we process the organic material in the shrimp farm before the next growing cycle?”.
Custom Biologicals uses bioaugmentation, the additional of specifically selected aerobic bacteria, to treat the organic constituents of shrimp farm wastewater. These bacteria have been selected because of their enhanced ability to metabolize the organic wastes in shrimp farms.