Gasping at the surface
Gasping at the surface.
Fish crowd at the surface, gulp air and breathe fast. Bettas, gouramis and other labyrinth fish normally take air at the surface; many fish doing it at once is an emergency.
- Do this first
- Test ammonia and nitrite now; if either is above 0, change half the water with dechlorinated, temperature-matched water.
- Call a vet when
- If fish keep gasping after water changes and aeration, gill disease needs a vet's diagnosis.
Likely causes
- Ammonia or nitrite poisoning
- Low oxygen: warm water, a stopped filter, no surface movement
- Gill damage or parasites
What to do today
- Test ammonia and nitrite now; if either is above 0, change half the water with dechlorinated, temperature-matched water.
- Add surface movement: point the filter outflow at the surface or add an air stone.
- Check the heater and filter are working and the tank is not too warm.
When to call a vet
If fish keep gasping after water changes and aeration, gill disease needs a vet's diagnosis. A vet who treats fish can examine it and prescribe treatment; your local fish store or aquarium society can often recommend one.
Stop it happening again
Test weekly, do not overstock, keep surface agitation. How to set up a quarantine tank.
Sources: Merck Veterinary Manual: Management of aquarium fish; Merck Veterinary Manual: Disorders and diseases of fish; UF/IFAS: Ammonia in Aquatic Systems.