Rainy / seasonal-change shrimp protocol — preventing WFS and acute stress

1. Why heavy rain is dangerous

Dual pressure occurs together:

• Salinity shock — rain drops salinity suddenly, disrupting shrimp osmoregulation.
• pH shock — rain pH 5.5 – 6.5 pulls pond pH down.
• Water stratification — fresh water on top, oxygen-starved bottom releasing toxic gases.
• Shrimp stress → gut imbalance → WFS appears within 3 – 5 days post-rain.

2. First-72h rapid response

Apply immediately after heavy rain ends:

• Measure pH and salinity — if pH < 7.5, lime CaCO₃ 10 – 15 kg/1,000 m³.
• Run aerators 24h continuous to break stratification + boost oxygen.
• Broadcast SOILMAX or MAX 4000 1 sachet/2,000 m³ to stabilize water.
• Feed: AQUAMOS 5 g/kg + TETRA-C 3 g/kg + LALPACK IMMUNE 3 g/kg, 2 meals/day, 3 days.
• Cut feed 30% for the first 48h — shrimp need time to adapt.

3. WFS prevention day 3 – 7

• Add CLEVER 3 g/kg + PRO GUT 3 g/kg for 5 days to protect the gut.
• Monitor green Vibrio on TCBS — if it spikes, broadcast VIBRIO CLEAR.
• Measure NH₃/NO₂ daily for 7 days — toxic gases rise sharply post-rain.
• Add minerals if moulting — shell weakness after rain stress.