Goldfish environment

Goldfish - A suitable environment


  • Should goldfish live in a tank or a pond? 
  • Where should a goldfish tank be positioned?
  • How can tap water be made safe for goldfish?
  • What temperature should the water be for goldfish?
  • Should gravel be put on the bottom of a fish tank?
  • Do goldfish need a filter in their water?
  • Do goldfish need an air pump in their tank?
  • How soon after setting the tank up can I put goldfish in it?
  • What’s the best way to add goldfish to the tank?
  • How often do I need to clean my goldfish tank out?
  • What’s the best way to clean my goldfish tank out?

Environment logo - a house

Should goldfish live in a tank or a pond? 


Goldfish need plenty of space to swim around in, so either a large fish tank or an outdoor pond is suitable. 

  • “Goldfish bowls” are not suitable housing for goldfish because they are usually too small and don’t allow enough oxygen to get in to the water.

Where should a goldfish tank be positioned?


The tank needs to be placed somewhere where the temperature stays fairly constant and that is out of direct sunlight and draughts. It should also be out of the reach of children and pets and away from vibrations (e.g. TV, music systems or passing footsteps). The tank needs to be placed on a polystyrene tile so that there is no unevenness beneath it.

How can tap water be made safe for goldfish?


Tap water contains chlorine, so needs to be made safe before goldfish can live in it. The most effective way is to add de-chlorination drops, available from pet shops. You should let the water stand for at least 15 minutes before adding it to the tank, so that it reaches the same temperature as the water it is being added to.

What temperature should the water be for goldfish?


Goldfish are classed as “coldwater” fish, which means they don’t need a water heater and they can live at room temperature in most homes. The water temperature shouldn’t change suddenly, and the fish shouldn’t experience extremes of heat or cold.

Should gravel be put on the bottom of a fish tank?


The bottom of a fish tank should be covered with safe gravel that has been well washed.

Do goldfish need a filter in their water?


A water filter is highly recommended. Water quality is the most important influence on fish health and without a filter, waste products can build up and make your fish susceptible to disease.

Do goldfish need an air pump in their tank?


The water that goldfish live in needs to contain enough oxygen for them. Oxygen enters the water from the air, at the water surface. Adding an air pump keeps the water circulating so that more oxygen can enter from the air, so it is recommended to use one. If you only have a small number of fish in a large tank, however, a pump may not be absolutely necessary, so ask a reputable retailer with good fish-keeping knowledge whether they recommend a pump for your situation.

How soon after setting the tank up can I put goldfish in it?


When you first set a fish tank up it needs a chance for the water quality to settle down. There may be high levels of dangerous substances before this has happened. Set the tank up, including turning the filter and pump on, and leave it running like this for at least 7 days before you add any fish.

What’s the best way to add goldfish to the tank?


When your tank is ready for fish, float the bag containing the fish in the tank water for 20 minutes to let them gradually become used to the new water temperature. Then add some water from the tank to the water in the bag, and wait another 10 minutes. Then let the fish swim in to the tank, and throw away the transport water and bag.

How often do I need to clean my goldfish tank out?


If you keep your goldfish in a tank you will need to change some of the water weekly, and regularly clean away any green algae that is growing. If there is any uneaten food floating in the water more than a few minutes after feeding, you should remove it with a net and feed less food next time.

What’s the best way to clean my goldfish tank out?


You should only remove 20 per cent of the water each time you clean the tank, unless your vet advises otherwise. Use a siphon to remove the water, then replace it with water that has had the chlorine removed using de-chlorination drops.

  • When cleaning your goldfish tank out, don’t replace all of the water with new water as this puts a lot of stress on their body which can make them unwell. Just change 20 per cent of the water at any one time.