TREATING AMMONIA TOXICITY IN AN AQUARIUM OR FISH POND

1) How do I know I have high ammonia levels in my aquarium or pond?

You will need to test the water for ammonia levels. The water may look clear and clean, yet still have high ammonia levels.Test kits are commercially available or your fish veterinarian can test the water for you. Always bring a separate container with a sample of your fishes’ tank/aquarium water to the veterinary consultation to submit for ammonia testing.

2) What are the clinical signs of ammonia toxicity in fish?

  • Increased mucous production

  • Red or bleeding gills

  • Body colour darkens

  • Increased respiration rates and fish seem to “gasp” air at the surface of the water

  • Secondary infections

  • Death

3) What is the immediate treatment for ammonia toxicity in fish?

  • Regular water changes (25-50%) to dilute the ammonia levels in the water.

  • Add chemical filtration

    • activated charcoal (for freshwater or marine tanks)

    • zeolite (for freshwater tanks).

  • Add commercial chemicals (e.g. ammo-lock)

    • These chemicals bind up the toxic ammonia(NH3) and change it to non-toxic ammonium (NH4+).

    • Note:any further ammonia tests will have a high result despite the ammonia now being temporarily non-toxic.

4) What other treatments may be necessary?

  • Add 1-2g/L salt to the water to relieve the stress on the kidneys of the fish.

  • Increase the oxygenation of the water by the addition of air stones to lower the chance of suffocation.

  • Decrease or stop feeding fish during a crisis as this will lower the amount of ammonia added to the water.

  • Decrease the number of fish in the tank.

  • Correct the temperature and pH over a few days to one week.

  • Antibiotics and other medications may be prescribed for secondary infections.

5) What further water testing will be necessary?

  • Retest ammonia levels every 1-3 days for the next 2-6 weeks.

  • Test nitrite and nitrate levels every 3-4 days for the next 6-8 weeks.

  • Continue to monitor pH levels daily for 6-12 weeks.