Maintaining optimal water quality is vital for successful shrimp farming, as poor conditions can lead to disease outbreaks, stunted growth, and mass mortality. This guide outlines the essential water quality indicators for shrimp ponds, their safe limits under international standards (FAO, ISO), and practical strategies for monitoring and management.
1. Dissolved Oxygen (DO)
- Importance: Supports shrimp respiration and beneficial bacteria.
- Optimal Range:
- FAO Guideline: 5–7 mg/L (daytime); >4 mg/L (night).
- Critical Limit: <2 mg/L causes hypoxia and shrimp mortality.
- Testing Tools: Optical DO sensors (ISO 5815-compliant), YSI ProDSS.
2. pH Level
- Importance: Affects ammonia toxicity and microbial activity.
- Optimal Range: 7.5–8.5 (FAO).
- Risk of Deviation:
- Low pH (<7): Increases toxic ammonia (NH₃).
- High pH (>9): Harms shrimp gills and molting.
3. Ammonia (NH₃/NH₄⁺)
- Importance: Highly toxic even at low concentrations.
- Safe Limits:
- Total Ammonia: <0.5 mg/L (OIE standards).
- Un-ionized Ammonia (NH₃): <0.02 mg/L.
- Testing Method: Colorimetric kits (ISO 7150-1) or digital meters.
4. Nitrite (NO₂⁻)
- Importance: Disrupts oxygen transport in shrimp.
- Safe Limit: <0.1 mg/L (FAO).
5. Salinity
- Importance: Affects osmoregulation and growth rates.
- Optimal Range:
- Pacific White Shrimp (Litopenaeus vannamei): 15–25 ppt.
- Black Tiger Shrimp (Penaeus monodon): 10–15 ppt.
- Testing Tools: Refractometers or conductivity probes (ISO 7888).
6. Temperature
- Importance: Influences metabolism and pathogen activity.
- Optimal Range: 28–32°C (82–90°F) for most species.
- Critical Threshold: >35°C (95°F) causes stress; <20°C (68°F) slows growth.
Parameter | FAO Guidelines | ISO Standards | OIE Recommendations |
Dissolved Oxygen | 5–7 mg/L | ISO 5815:2003 (DO measurement) | - |
Ammonia | <0.5 mg/L (total) | ISO 7150-1 (ammonia testing) | <0.02 mg/L (NH₃) |
pH | 7.5–8.5 | ISO 10523 (pH measurement) | 7.2–8.5 |
Salinity | Species-specific | ISO 7888 (conductivity method) | - |
1. Multi-Parameter Water Quality Meters
- Examples: ERUN-SP7
- Features: Measures DO, pH, salinity, temperature, and ammonia.
- Compliance: Aligns with ISO 5815 and ISO 10523.
2. IoT-Based Sensors
- Remote Monitoring: Systems like ERUN Multi-parameter water quality monitoring system track real-time data and alert for critical changes.
- Benefits: Reduces manual testing and prevents sudden parameter shifts.
1. Daily Monitoring:
- Test DO, pH, and temperature twice daily (dawn and dusk).
2. Weekly Water Exchange:
- Replace 10–30% of pond water to dilute toxins (ammonia, nitrite).
Adhering to FAO, ISO, and OIE water quality standards is non-negotiable for profitable and sustainable shrimp mariculture. By integrating real-time sensors, probiotics, and routine testing, farmers can prevent crises and optimize yields.
