If your tetra is swimming sideways, it is likely suffering from a swim bladder disorder. This organ controls buoyancy, and when it malfunctions, fish may float, sink, or tilt. The most common causes are overfeeding, constipation, poor water quality, or infection. Here is how to address it.
Immediate Steps to Take
First, observe your tetra for other symptoms: bloating, clamped fins, or labored breathing. Check your water parameters with a test kit: ammonia and nitrite should be 0 ppm, nitrate under 20 ppm. Perform a 25% water change if levels are off. Next, stop feeding for 2-3 days to allow digestion. After the fast, offer a blanched, skinned pea (mashed) to relieve constipation.
Adjusting Diet and Feeding Habits
Overfeeding is a leading cause. Feed small amounts once or twice daily, only what they consume in 2 minutes. Use sinking pellets or flakes designed for tetras. Consider fasting one day per week. If constipation is recurrent, add daphnia or brine shrimp for fiber. Avoid freeze-dried tubifex worms which can cause bloat.
Improving Aquarium Conditions
Stress from poor water quality or sudden temperature shifts can trigger swim bladder issues. Keep the tank at 74-78°F with a gentle filter flow. Perform weekly partial water changes of 20-30%. Avoid overstocking: tetras need at least 2-3 gallons per adult fish. Add aquarium salt (1 tsp per 5 gallons) to reduce osmotic stress and aid recovery.
When to Consult a Veterinarian
If the sideways swimming persists after 4-5 days of fasting and water improvements, a bacterial or parasitic infection may be the cause. A vet can prescribe antibiotics like kanamycin or metronidazole for internal infections. Watch for white spots, redness, or swelling. Quarantine affected fish if possible. For severe cases, veterinary intervention is necessary.
Key Takeaway
Stop feeding your tetra for two days, check water quality, and offer a peeled pea to address constipation related swim bladder issues.