Swimming sideways in Asian Stone Catfish (Hara jerdoni) is a critical sign of distress, often indicating a serious health issue. This behavior can be life-threatening if not addressed promptly. Owners should first ensure water parameters are within the optimal range for this species.
Common Causes of Swimming Sideways in Asian Stone Catfish
Poor Water Quality
Most LikelyHigh ammonia or nitrite levels can cause stress and muscle weakness, leading to sideways swimming.
Infection
Most LikelyBacterial or parasitic infections can impair motor control and cause the fish to swim abnormally.
Physical Injury
PossibleImpact or injury to the spine or muscle can result in uneven swimming patterns.
Malnutrition
PossibleLack of essential nutrients can weaken the fish, making it difficult to maintain balance while swimming.
Stress
Less CommonEnvironmental stressors such as overcrowding or sudden changes in water conditions can cause behavioral changes including swimming sideways.
How to Diagnose
Follow these steps in order. Stop when you identify a likely cause and move to treatment.
- Perform a visual inspection
Check for signs of injury, such as fin damage or lesions.
Recommended: null - Measure water parameters
Test for ammonia, nitrite, nitrate, pH, and temperature levels.
Recommended: Water testing kit - Observe feeding and behavior
Note if the fish is eating and how it interacts with its environment.
Recommended: null - Perform a physical examination
Gently examine the fish for any physical abnormalities.
Recommended: net or cup - Consider a water change
If water quality is suboptimal, perform a partial water change to improve conditions.
Recommended: siphon or bucket
How to Fix It
- Improve water quality
Adjust pH and temperature, and remove any sources of ammonia or nitrite.
- Treat for infections
Use appropriate medications, following label instructions, if infection is suspected.
- Provide a stable environment
Avoid sudden changes and ensure adequate space for swimming.
- Ensure proper nutrition
Feed a balanced diet rich in essential nutrients and vitamins.
- Monitor progress
Regularly observe the fish for signs of improvement or worsening of symptoms.
Prevention
When to Seek Expert Help
📖 Full Care Guide
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This guide was reviewed for biological accuracy and practical aquarium care guidance. Always test water parameters before treating a sick fish — poor water quality is the most common root cause. Consult an aquatic veterinarian if symptoms persist after 48 hours of correct treatment.