Stock pond management in brackishwater system is essential for good productivity. Brackish water culture involves the production of prawns or local fish in a controlled environment. The business is very viable because the prawns or shrimps have good local and export market. 70% of prawn culture in India is traditions system of farming.
Things that affect Brackishwater system
Brackishwater systemare usually free flowing systems or cordoned waterways. Due to the constantly changing water there are different changes in the water. Changes include water salinity, depth, physiochemical changes. Others are turgidity, water temperature, organic matter, and dissolved oxygen or ph. levels.
More conditions are accumulated feed, fish water or pollution are real issues. Stock pond management in these conditions is crucial to the production or survival of marine life. Abrupt changes may cause huge losses through death of the fish stock.
Challenges in Brackishwater system
- water salinity
- water depth
- physiochemical changes
- water temperature
- organic matter
- dissolved oxygen
- ph. Levels
- accumulated feed
Types of fish stocked in brackish pond
The type of fish stocked in brackish pond depends on local aquatic life. Saltwater supports only saltwater fish, shrimps or prawns.
Type of Aquatic life in brackishwater culture
- Stocked fish
The first step in brackishwater aquaculture is selection of site. The site should have good tidal flow, nice topography, wave action, tidal fluctuation. Others are favorable environmental, biological factors, reduced cyclic hazards and abundant seed opportunities.
- good tidal flow
- nice topography
- wave action
- tidal fluctuation
- favorable environment
- biological factors
- reduced cyclic hazards
- abundant seed opportunities
Cordon an area and evacuate to hold water 80cm with pond area 0.5 ha. Construct peripheral dyke and compact soil to withstand tidal pressure and good water retention. Introduce a flushing system and fertilize when appropriate. Make sure the dissolved oxygen content can sustain aquatic life.
Seed procurement is mostly harvested from the wild. Look for aquatic life already sustained in the same geographical location. Another way to acquire seed is from research institutions in your geographical location.
Management of Stock Pond
Most brackishwater systems are saltwater systems feed by the sea or ocean. Therefore proper management of the system is essential to sustain aquatic life. Use mechanical means to flush pond water at intervals into the pond system.
Another method is to let-in tidal waves to flush the system. Make sure the aquatic life are escape proof and the water is well aerated at all times. It is important to maintain pond depth of 80 cm to allow photosynthesis occur, maintain water salinity at 20pp with good dissolved air for better yield.
Disease and Predators
Secure the aquatic life from predation or escape. Remove excess feed, waste matter, maintain water salinity. Avoid low oxygen levels, turgidity and pollution will kill the aquatic life.
The method of harvesting is introduction of net and partial draining of pond. Only the fully grown and matured aquatic life is removed and smaller ones returned to the system.