Is my shrimp ill? Assessing behaviour and appearance

Assess change relative to the normal behaviour of the same animal or group. Paler colour, hiding or a brief pause in grazing does not establish disease. Loss of balance, rapid deterioration or several animals affected together does require prompt action.

Observe without disturbance

• Watch posture and movement: can the animal hold position and move normally? Do not repeatedly touch it to provoke a response.
• Record food uptake and feeding style. A fan shrimp filters in a current and need not show the grazing pattern of Neocaridina.
• Describe any new patch: outside or within the body, colour, shape and position. Take comparable photographs rather than diagnosing from an internet image.
• Assess the group pattern. Is one animal different, or is the change distributed through the aquarium? Record counts and times.
• Check recent capture, transport, molting, tankmates and changes in lighting or furnishings. These are investigation points, not automatic explanations.

Hiding or molting

A hidden animal cannot be declared healthy from outside. Leave quiet shelter intact while following the rest of the group and subsequent progress. For an empty shell, see molt versus carcass. Do not pull the shell if a living animal appears trapped.

Judge urgency from the course

Loss of balance, repeated deaths or several severely affected animals calls for immediate checks of temperature, filtration, gas exchange, ammonia and nitrite. Use the emergency plan and seek informed help promptly. A complete photograph series or every additional test need not come first.

For one otherwise functioning animal, make a baseline record and compare later observations. Seek assessment if the change persists, spreads or food uptake declines. Normal routine readings do not exclude infection or unknown contamination. Discuss isolation as a housing decision, not a diagnosis or automatic treatment.

Sources and scope

• LICG: Zoetwatergarnaal
• Merck Veterinary Manual: Management of Aquarium Fish
• Aqueon: Freshwater shrimp, bamboo-shrimp feeding
• Kelleher & Mykles: Characterization of the Neocaridina davidi molt cycle

The sources support general husbandry, clinical observation and species-specific behaviour. The molt research concerns a particular Neocaridina experiment. Our observation list is not a validated disease test or a deadline for every animal to molt.