Deep beneath the surface of the pond lies the bottom sludge layer, where large amounts of organic and inorganic matter accumulate. If not properly managed, bottom sludge will become a “ticking time bomb,” generating toxic gases, degrading water quality, triggering disease outbreaks, and seriously affecting production yield.
POND BOTTOM SLUDGE – HOW IT FORMS AND THE HAZARDS IT POSES
Bottom sludge does not form on its own; it is created from:
- Excess feed, fish waste, dead algae.
- Soil, sand, and silt carried in by the water supply.
As it accumulates over time, this sludge becomes anaerobic, promoting the growth of anaerobic bacteria and producing toxic gases:
- H₂S (Hydrogen sulfide): a rotten egg smell, suppresses respiration, and can cause mass fish mortality.
- NH₃ (Ammonia): causes shock and weakens the immune system.
- CH₄ (Methane): not directly toxic, but reduces dissolved oxygen, causing fish to suffocate.
THE DOUBLE IMPACT: POOR ENVIRONMENT – DISEASE OUTBREAKS
- Water deterioration: bottom sludge consumes dissolved oxygen, causing nighttime oxygen depletion; when disturbed, it also makes the water turbid, blocks light, and causes pH fluctuations.
- Potential disease reservoir: nutrient-rich, oxygen-poor sludge is an ideal refuge for Vibrio bacteria, fungi, and parasites. When fish are stressed, they are easily attacked, leading to disease outbreaks and economic losses.
SUSTAINABLE MANAGEMENT SOLUTIONS
Relying only on sludge dredging at the end of the production cycle is costly and does not solve the root cause. Farmers need to shift from “reactive treatment” to proactive management by:
- Strictly managing feed to minimize waste.
- Maintaining paddle wheels and aeration systems to increase oxygen and support aerobic microorganisms in safely decomposing organic matter.
- Regularly adding probiotics to break down sludge, reduce toxic gases, and simultaneously compete with and inhibit pathogens.
TOWARD A SAFE, EFFICIENT CULTURE SEASON
Managing bottom sludge is a decisive factor in pond stability. Implementing the above measures in a synchronized manner not only helps reduce medication costs and limit disease risks, but also improves product quality, meets safety standards, and increases market value.
NTS
Source: https://tepbac.com/
