Caring for your Goldfish

Like all pets, Goldfish need your care to keep them happy and healthy. Our vets have lots of advice about how to care for your aquatic friends.

Giving your goldfish the perfect home

Goldfish need plenty of space to swim. A large fish tank or an outdoor pond will give them the space they need to live a happy, healthy life.

‘Goldfish bowls’ don’t make good homes for fish - they’re are usually too small and don’t let enough oxygen into the water.

Goldfish are cold-water fish, so they don’t need any special equipment to heat up their tank. It’s important not to change the temperature of the tank suddenly as this can shock your fish.

Goldfish are social animals so they need other fish to keep them company. Be careful not to keep too many together in one tank as this can lead to bullying and their water can become polluted. As a general rule of thumb, you can keep 0.5cm of fish per litre of water in the tank.

Here are more ways to transform your tank or pond into a fish’s paradise:

  • Keep your fish tank somewhere where the temperature will stay fairly constant. It should be out of direct sunlight and draughts. Make sure it’s out of reach of children, other pets, and away from vibrations (e.g. the TV or sound systems).
  • Place your tank on polystyrene tiles so it’s on an even surface.
  • We highly recommend using a water-filter because water quality is really important for the health of your fish. Without a filter, waste products can build up in the tank and make your fish ill.
  • Adding a pump will keep the water moving so that more oxygen can get into the water from the air. We recommend adding one to your tank or pond but if you only have a few fish in a large space it might not be necessary. If in doubt, speak to a specialist with good fish-keeping knowledge.
  • Cover the bottom of the tank with safe gravel. Rinse it well before you add it to the tank.
    Adding objects and ornaments to your tank can help keep your fish active and help them feel safe. Shelters such as caves and tunnels will let them get away from other fish when they want to. Plants and other objects will add interest and give them something to explore. Don’t add too many things to their tank, though – they still need plenty of space to swim around freely.
  • When you fill your tank, you’ll need to make the water safe for your fish. Tap water has chlorine in it which is dangerous to fish. You can add de-chlorination drops (available from pet shops) to make the water safe.

Adding your goldfish to their tank

Once you’ve got the tank set up, and it’s been filled with de-chlorinated water, you’re ready to add your fish to their new home!

  • Float the bag containing your fish in the tank water for 20 minutes to let your fish gradually get used to the new water temperature.
  • Add some water from the tank to the water in the bag and wait another 10 minutes.
  • Let your fish swim into their new tank and throw away the water from the bag.

Cleaning your goldfish tank

You’ll need to clean your fish tank regularly to stop waste products building up in the tank and making your fish ill.

Daily cleaning:

You can clean away any uneaten food after feeding time by removing it with a net.

Weekly cleaning:

  • Remove around 20% of the water from the tank and throw it away.
  • Clean away any green algae growing in the tank.
  • Treat the replacement water with de-chlorination drops and leave to sit for 15 minutes so that it reaches the same temperature as the tank. Carefully add it to the tank.
  • Unless told to by your vet, don’t change all the water in the tank at once. This can put a lot of stress on your fish.

Feeding your goldfish

Goldfish should be fed a good quality complete commercial goldfish food. Complete foods contain all the nutrients your fish need and often come in flakes which are easy to measure out and feed to your fish.

Always follow the feeding guidelines on the food packet. Generally, goldfish should be fed twice a day. If there is any uneaten food left in the water a few minutes after feeding, you’re feeding them a bit too much in one go. Use a net to remove the uneaten food and give them a bit less next time.

Goldfish health

Check your goldfish every day for any signs that they’re getting sick. Look for:

  • Gasping at the surface
  • rubbing against objects in the tank
  • lethargy
  • not eating
  • swimming in an unusual way
  • changing colour
  • lumps or ulcers
  • any growths that look like cotton wool
  • damaged fins.

If you see any of these signs, visit your vet straight away. Any change in the way your fish look or act could be a sign of illness – if in doubt, speak to your vet.

If your local vet is reluctant to treat fish, you can find a vet who is knowledgeable about fish here.