Guide to Goldfish Tank Equipment

If your goldfish are to thrive and live a happy life, you’ll need the correct kit for their tank. 

In this guide, we explain just what you’ll need to set up and maintain the ideal home for your fishy friends.

What equipment is needed for goldfish?

Here’s a detailed list of the equipment you’ll need for your goldfish setup:

  • Tank
  • Filtration system
  • Lighting
  • Air pump and air stone
  • Aquarium water testing kit
  • Tap water conditioner
  • Aquarium vacuum cleaner
  • Algae magnet

It’s worth noting that many tanks come as a kit containing many of the essential items you need to get started, as well as some extras, such as gravel, fish food and artificial plants.

However, if you prefer to customise your goldfish tank, you can find everything you need for your aquarium at your local pet store or fish shop.

What equipment do you need to set up a fish tank?

Now, let’s look in more detail at the equipment you’ll need to set up your goldfish tank.

Fish Tank

First of all, we must stress that you should keep goldfish in a tank, not in a bowl

Goldfish of all types can grow pretty large, and a traditional goldfish bowl doesn’t provide sufficient swimming space for the fish once they’re fully grown. 

Goldfish are oxygen-hungry fish, and a round, bowl-shaped container doesn’t have a big enough surface area for efficient gaseous exchange. We recommend a rectangular-shaped fish tank for goldfish, as that provides plenty of surface area and swimming space.

Goldfish are sociable creatures that are happiest when kept in the company of their own kind. So, goldfish should always be kept in small groups or pairs, never alone.

The minimum tank size for goldfish should be 20 US gallons / 75 UK Litres for the first fish. Add 10 gallons (37L) to the tank’s capacity for every additional goldfish.

Although adult Fancy Goldfish aren’t generally known as jumpers, the tank should have a lid or a cover slide to prevent dust from contaminating the water and preventing any unexpected escapes!

Our suggested starter tank for Goldfish

Glass or Acrylic?

Larger fish tanks are usually made from glass. However, you can sometimes find 20-gallon acrylic tanks. 

Both materials have pros and cons:

  • Glass is heavier and more expensive than acrylic. 
  • Glass is stronger and less likely to get scratched during cleaning than acrylic. 
  • Glass tends to keep its clear outlook, whereas acrylic can take on a yellowish tinge over time, spoiling your view of the fish. 
  • Acrylic is less likely to crack or shatter than glass in the event of an accident. 

We recommend a glass tank of the two materials, as they tend to last longer than acrylic if you buy a good quality one.

Filtration System

Goldfish are dirty fish that create lots of waste, so you’ll need an efficient filter system to process the waste and keep the water safe for your fish.

There are several different types of filter systems that are commonly used in home fish tanks. Here are some of the best filters for goldfish tanks:

HOB (Hang-On-Back) Filter

As you might expect from the name, HOB filters are external filter units that you fix to the back of your tank. 

All the filter media and other paraphernalia are housed inside a plastic casing. Water is drawn from the tank, passed through the filter media, and returned to the tank via a cascade, waterfall outlet effect.

HOB filters can be a good choice for a goldfish tank. They don’t take up any space inside the tank, and the water effect return system agitates the water surface, helping to oxygenate the water.

Internal Filter

Like the HOB filter, everything is housed inside a plastic casing. Internal filters live inside the tank, usually fixed to the glass by rubber suckers. Water passes through the unit, over the filter media, and out again via an outflow.

Internal filters are not the best choice for goldfish, as they hog too much space in the tank, and cleaning them can be a messy business. The outflow of many internal filter systems can generate too much flow for slow-swimming Fancy goldfish to be comfortable.

Canister Filter

Canister filters are large, external filter units that are usually kept in the cabinet underneath your aquarium.

The tank water passes through the filter unit, where it’s cleaned and then returned to the tank. Canister filters can be a good choice for a large goldfish tank.

These filters don’t take up any space in your tank, are powerful enough to process the organic waste produced by a goldfish tank, and the filter media you use can often be customised.

Undergravel Filter

Undergravel filters consist of a large filter plate that sits underneath the substrate, a vertical tube, and a separate air pump.

The tube drags water down through the substrate and underneath the plate before passing the water back up the tube. That creates a water flow through the substrate that pulls organic waste down and promotes the growth of aerobic bacteria in the substrate. That effectively turns the whole gravel bed into a biological filter.

The main disadvantage of undergravel filters is that you need to take the whole tank down annually to clean the area underneath the plate. Since goldfish are such dirty creatures, an undergravel filter is not the best choice.

Sponge Filter

A simple sponge filter consists of a box containing some filter media and an air pump that pulls the tank water through the filter before returning it to the tank.

Sponge filters are usually used in spawning tanks where there are vulnerable fry and are not really powerful enough for a goldfish tank.


Goldfish appreciate eight to ten hours of lighting in their tank to replicate nature’s day/night cycle. If you have live plants in your goldfish tank, they will need lighting for photosynthesis. 

The lights should come on in the morning, telling the fish that it’s time to wake up and feed. In the evening, the lights should be turned off so that the fish know it’s time to rest.You can buy lighting units with built-in timers or use a simple plug-in timer that you can get from your local DIY store.

Air Pump and Air Stone

As mentioned earlier, goldfish need lots of oxygen in the water to remain healthy and thriving.

Your filter system can provide some oxygen by agitating the water surface, but an air stone makes a useful addition. All you need is a simple air pump, a length of airline, and an air stone. The pump pushes air down the airline and out through the air stone, aerating the water.

Position the air stone in one corner of the tank so the fish don’t disturb it.

The Air Pump we recommend is:

Aquarium Water Testing Kit

To ensure that your goldfish tank water is safe for your fish, you need to test the water every week. 

Nitrate levels in the water should be 30ppm or less, while ammonia and nitrites should be at zero.

Use a proper aquarium water testing kit that you’ll find in your local fish store.

Tap Water Conditioner

Tap water contains chlorine and chloramine, which are highly dangerous to goldfish.Before you add tap water to your fish tank, you must add some tap water conditioner that makes the water safe for the fish. When choosing a tap water conditioner, double-check that the product treats chlorine and chloramine.

Aquarium Vacuum Cleaner

An aquarium vacuum cleaner works by sucking out organic waste matter from the fish tank. Push the cleaner down into the substrate and move it around to dislodge solid matter, which is then removed from the tank.

Using an aquarium vacuum cleaner as part of your weekly tank cleaning routine will relieve some of the load on your filter system and keep the environment clean for the fish by removing organic matter that would otherwise rot and pollute the water.

Algae Magnet 

Although goldfish graze on algae during the day, you don’t want your viewing panes covered with green slime, so you need to clean them with an algae magnet every week.

An algae magnet is a two-part cleaning system. The smooth magnet is drawn down the outside of the glass while the rough scraper cleans the glass on the inside.

How to clean fish tank equipment

In this part of our guide, we look at how to clean your fish tank equipment.

Do not use harsh household cleaning chemicals to clean anything that lives inside your fish tank! Any residue left on the item could seriously harm your goldfish.

Cleaning Your Fish Tank

A new fish tank should be rinsed in warm tap water to remove dust and then dried thoroughly with a clean paper towel. You can use glass cleaner to polish up the outside of the glass, but take care not to get any of the cleaner inside the tank.

If you need to take down an existing tank to clean it, first use warm tap water to rinse the tank clean of debris and fish waste. Use a mild white vinegar and water solution to gently clean the inside of the tank and remove algae from the viewing panes. 

Rinse the tank thoroughly with warm tap water.

Take care not to disturb the sealant that fixes the panes of glass together. Before replacing your decorations, plants, and fish back in the tank, fill it with water and wait an hour or so to be sure that the tank doesn’t leak.
Once you have your tank set up, you can read our full tank cleaning guide to ensure you keep up with crucial maintenance.

Cleaning Your Filter System

Your filter system can accumulate deposits of sludge and algae over time, so you’ll need to clean it once every few weeks or so to keep the system clear and running efficiently.

  • Turn off the filter pump and remove the filter media. 
  • Rinse the media in old tank water to remove debris.
  • Use an old toothbrush or filter cleaning brush to scrub algae and sludge from the filter box and associated tubes.
  • Rinse the filter box and tubes in old tank water.
  • Reassemble the filtration system and media, and replace the unit in your tank.

Remember to switch the filter back on! Check that the unit is working correctly.

Once a month or so, in line with the manufacturer’s instructions, replace spent filter media.

How to sterilise new fish tank equipment

If you buy a new filter for your fish tank, it’s a good idea to sterilise it before use. Sterilising the unit helps to get rid of any bacteria that might be present so that you don’t accidentally introduce them to your fish tank.

You can use a solution of white vinegar and water or a very mild solution of bleach and water to sterilise your new filter. Make up the solution of 1 part vinegar or bleach to 20 parts water and wash the filter box and tubing in it.

Rinse everything thoroughly afterward in warm tap water to remove any residual chemicals.

Do not wash the filter media. Exposing the filter media to vinegar, bleach, or tap water could hinder the growth of the bacterial colonies you need to process any ammonia in the water. Without those bacteria, your fish tank won’t cycle, and the tank will not be safe for your fish.

What equipment do you need for a tropical fish tank?

A tropical fish tank needs the same basic equipment as a cold water goldfish tank. However, to keep tropical fish, you also need a water heater.

Tropical species come from areas of the world where the water temperature is typically between 75°F and 82°F or even more. In contrast, goldfish prefer cold water of a temperature between 68°F to 74°F. 

Water heaters can be incorporated into internal filter systems or used as stand-alone units that fix to the glass inside the tank by means of rubber suction cups. The heater has a thermostat that regulates the water temperature to a preset limit that you can set to suit the needs of your fish.

Final Thoughts

Did you enjoy our guide to the equipment you need for your goldfish tank? If you did, please share the article.

As well as a tank for your goldfish, you’ll need other essentials, including a filter system, lighting, cleaning equipment, a water testing kit, and some tap water conditioner. If you want to keep tropical fish, you can add a water heater to that list of essential supplies.

What kind of filter system did you choose for your goldfish tank? Tell us in the comments box below.

3 thoughts on “Guide to Goldfish Tank Equipment”

  1. “Once a month or so, in line with the manufacturer’s instructions, replace spent filter media.” – Sorry, this is so wrong. Media should only be changed when it is falling apart – and that is both mechanical and biological. Manufacturers only tell you to replace so they can make money.

  2. Hi there! We are looking to keep a 20 gallon fish tank on our patio. Problem is, we have no outlet outside and we rent, so there isn’t much we can do about it. I was thinking about battery operated pumps/filters and all of those things, but it seems that those are mostly for emergencies and solar powered ones seem finicky. Are there any options for those of us that want to keep an outdoor fish tank with no electricity?

    • Hi Alison,

      They do USB air pumps online which you can buy fairly cheap, which you can link to a solar powered plug, although like you said they can be a bit finnicky at times, but its certainly worth a try.

      sometimes for a decent size pond, we can get away without the use of electricity and filtration, but in a 20 gallon tank, it is not really doable, especially not with goldfish.

      To compromise for the lack of electricity would come at the cost of the goldfishes wellbeing, and we would say its not really worth it.

      perhaps try something else, like raising tadpoles or growing pond plant in there instead, it would make a nice feature and you can get much enjoyment from it.

      hope this helps


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