June 3

Sarah Robertson

Goldfish Tank -Complete Guide to Successful Goldfish Care

Goldfish are one of the most popular pets in the world and are enjoyed by people of all ages. They come in a wide variety of colors, shapes, and sizes and can make a great addition to any home. Goldfish are fairly easy to care for, but there are a few things you should know in order to keep your goldfish healthy and happy. The first is knowing how to set up a Goldfish tank.

Though people often think that any old fishbowl will do, this is actually not the case. A goldfish bowl might be fine for a betta fish or a goldfish fry, but an adult goldfish needs more than that. This guide will teach you everything you need to know about setting up a goldfish tank, including what size tank you need, what kind of filtration to use, and what kinds of plants and decorations to add.


Crossbreeding wild carps resulted in the creation of goldfish. Something strange happened while carp was still raised for food. Carp developed genetic changes, some of which acquired brilliant red, yellow, and orange hues. If these fish were in the wild, they'd be preyed on right away because they stood out so much. Buddhist priests noticed this new generation of bright-colored fish in the 9th century and started breeding them.

At first, goldfish were only kept by Chinese nobility, but they eventually became popular among the general public. In the 18th century, goldfish were introduced to Japan and then Europe. By the 19th century, they had made their way to North America.

Today, goldfish come in a variety of colors and shapes. The most common goldfish colors are orange, white, red, and yellow. Blue and black goldfish are less common but still available. You can also find goldfish with different patterns, like calico or bi-color. Goldfish come in a variety of shapes, too. The three main types are Comets, Commons, and Fantails.


Goldfish are hardy fish species with an average lifespan of  10-15 years. That being said, some have been known to live up to 30 years in captivity.

The key to a long and healthy life for your goldfish is providing them with proper care. This includes a clean and well-filtered tank, a healthy diet, and regular vet check-ups.


Goldfish can grow to be quite large, up to 18 inches in some cases. However, the average size of a goldfish is between 4-6 inches.

The size of your goldfish will depend on the type of goldfish you have. Some, like Comets and Commons, can grow to be quite large, while others, like Fantails, stay relatively small.


A healthy and balanced diet is essential for a long and happy life for your goldfish. Goldfish are omnivores, which means they eat both plants and animals.

A good diet for a goldfish includes:

  • Tubifex Worms

  • Brine shrimp

  • Daphnia

  • Bloodworms

  • Vegetables like lettuce, spinach, and zucchini

  • Fruit like grapes and melon

You can also give your goldfish pellets or flakes, but make sure they are high quality and do not contain fillers like corn or wheat.

Goldfish Tank Setup

Goldfish Tank Setup 

Goldfish are relatively easy to care for, but there are a few things you need to know in order to keep your goldfish healthy and happy. The first is knowing how to set up a Goldfish tank.

Goldfish Tank Size

Although many individuals believe that any old fishbowl will suffice, this is not the case. A goldfish bowl may be adequate for a betta fish or a goldfish fry, but an adult goldfish requires more space.

The Common Goldfish can grow up to 10 inches in length, while the Fancy variety can reach 8 inches. That's a lot of Goldfish for a tank! The mass of goldfish, especially the Fancy types, is significant. It's no surprise that goldfish were originally kept in ponds because of their adult sizes.

When sizing an aquarium for your goldfish, you must take into account the length, height, and width of the fish. As a rule of thumb, you should allow for at least 20 gallons of water for a small group of fish.

Goldfish Tank Filtration

Goldfish are large, messy, eat constantly throughout the day, and stir up your Aquarium Substrate all day. Therefore, a good filtration system is essential for a goldfish tank. A filter will help to remove waste and keep the water clean and clear.

There are a few different types of filters you can choose from, including:

  • Undergravel filters
  • Canister filters
  • Hang-on-back filters
  • Sponge filters

The type of filter you choose will depend on the size of your tank and the number of goldfish you have.

Goldfish Tank Parameters (Water Quality and Goldfish) 

Goldfish are tolerant of a wide range of water conditions, but there are a few things you should keep in mind:









Water Hardness:

5-20 dGH

The most important thing when it comes to Goldfish tanks is to check your Nitrate and pH levels on a regular basis after the tank has been cycled. When you first cycle the tank or add new fish, ammonia is generally a concern. Due to their messiness and constant hunger, goldfish produce a lot of waste.

Because of this, a goldfish pond will typically have higher nitrate levels. A suitable Aquarium Test Kit should be used to check your nitrate levels on a regular basis. Keep an eye on your goldfish's nitrates by ensuring that they never exceed 40 degrees. This will guarantee the best water quality for you and your fish.

Goldfish Tank Temperature

Goldfish are cold-water fish. A Goldfish's ideal range is 65-72 degrees Fahrenheit, which means anything higher than 75 degrees for a goldfish will put your fish under stress.

Goldfish can survive in temperatures as low as 50 and as high as 75 degrees Fahrenheit, with the average temperature being 65-72 degrees F. This implies that your home's water temperature should never be too hot or too cold for a goldfish.

Aquarium Heaters are only necessary if the room your fish is kept in is particularly cool or if you plan on housing tropical fish with your goldfish. A good rule of thumb is to never heat more than 10 degrees above the ambient room temperature.

Goldfish Tank Substrate

Goldfish are bottom-feeders and love to sift through Aquarium Substrate in search of food. A good substrate for a goldfish tank is one that is coarse and will not break down easily. Some goldfish keepers prefer to use sand as their substrate, but this is not recommended as it can be easily ingested by your fish and cause health problems.

Goldfish Tank

Aquarium Plants 

Although live plants are not a necessary addition to a goldfish tank, they can provide your fish with hiding spots and help to oxygenate the water. If you choose to add live plants to your tank, be sure to select plants that are hardy and can tolerate the waste produced by goldfish. Some good plants for a goldfish tank include:

  • Anacharis
  • Hornwort
  • Java Fern
  • Water Wisteria

Plants can also be used to help control nitrate levels in your tank by absorbing excess nutrients from the water. This is known as the Nitrogen Cycle. However, make sure not to overcrowd the fish tank with plants as they require plenty of space to swim around.

Goldfish Tank Decorations

Goldfish enjoy exploring their tanks and will appreciate hiding places as well as areas to swim through. However, this varies based on the sort of goldfish. Goldfish are known for their speed; they enjoy swimming.

Fancy Goldfish are sluggish, clumsier, and have more delicate fins than Common Goldfish. Both sorts of Goldfish require a lot of room to swim. When constructing a Goldfish tank, consider including an open aquascape.

When it comes to Decorating a Goldfish Tank, both size and safety must be considered. Any decorations you put in your tank should be too large for your fish to swallow and must be smooth to prevent injuries. Some safe and suitable decorations for a goldfish tank include caves, rocks, driftwood, and live plants.

Goldfish Tankmates 

Goldfish have a lot of requirements when it comes to tank mates. They are normally very peaceful fish and so it is difficult to find compatible companions for Goldfish in tanks. They are cold-water fish, so they cannot live with tropical freshwater fish.

The fancy goldfish also has a slow swimming speed and large fins, which may attract nipping from a more active fish. Goldfish might become bullies as well. Their size, mouths, and bulk can be challenging for smaller fish due to their aggressiveness. As a result, the finest advice is to keep only one Goldfish in an aquarium.

That being said, certain tank mates would be compatible. These tank companions are:

  • Cories
  • Guppies
  • Koi Fish
  • Mollies
  • Platies
  • Nose Plecos
  • Snails

Compatible invertebrates include:

  • Crayfish
  • Shrimp
  • snails

Snails are beneficial since they can be used to clean the tank of algae and, in most cases, Goldfish should leave them alone. If the Goldfish become irritated with them, they are big enough to defend themselves and allow you time to reconsider their compatibility. After all, each individual Goldfish is unique.

It's usually better to introduce new fish and inverts after the goldfish have been introduced. You'll want to make sure your goldfish are comfortable since they're more often the ones that are bullied, not vice versa! If you want to keep other tankmates, a larger aquarium (55 or 75 gallons) would be ideal.

Aquarium Maintenance

Aquarium Maintenance

A well-maintained tank is essential for the health and happiness of your goldfish. They help to remove toxins and waste from the water, as well as replenish essential minerals. Depending on the size of your tank and the number of fish you have, water changes should be carried out every one to two weeks.

Scheduled aquarium maintenance would not be complete without the water change. An average water change of 10 – 15%, every two weeks, is often sufficient for most tanks. Larger tanks or those with a high stocking density of fish may require more frequent water changes.

To perform a water change:

  • Remove any decor, plants, or gravel from the tank.
  • siphon out 10 – 15% of the water into a clean bucket. If you do not have a siphon, you can use a cup or pitcher.
  • With a clean cloth, wipe down the inside of the tank, being sure to remove any algae or build-up.
  • Replace the decor, plants, and gravel.

  • Fill the tank with freshwater, using a water conditioner to remove any chlorine or chloramine.

  • Once the tank is full, turn on the filter and heater.

  • Allow the tank to cycle for 24 hours before adding fish.

To clean the aquarium glass:

  • Use an algae scraper or sponge to remove any algae growth from the glass.
  • Fill a bucket with 1 part water and 1 part vinegar.
  • Dip a clean cloth into the bucket and use it to wipe down the glass.
  • Rinse the glass with clean water.
  • Repeat steps 2-4 as necessary.

To clean the gravel:

  • Siphon out 10 – 15% of the water into a clean bucket.
  • Use your hands to gently stir the gravel and remove any build-up or debris.
  • Rinse the gravel with clean water.
  • Repeat steps 1-3 as necessary.


Water in a city might be chlorinated or chloraminated (treated with chlorine or chloramine). If the water is left in an aerated bucket for 24 hours, it will air out. Chloramine will not do this. Chloramine is made up of chlorine and ammonia.

Either way, chlorine should be neutralized with a water conditioner. Even after treatment with a conditioner, ammonia will stay in the water if it contains chloramine. After adding the water to the aquarium, nitrifying bacteria will break down the ammonia.

Overcrowding of the aquarium, as well as overfeeding, can be harmful to the fish. The extra excrement will make it more difficult to keep a healthy fish tank.

Other substances in municipal water include phosphates, iron, and other heavy metals. Consult your water company to determine whether the water is suitable for use in your aquarium.

Well, water, on the other hand, is typically harder than municipal water. It should, however, be free of chlorine and chloramine.

Even if you're using filtered water, it's a good idea to check it for critical readings on a regular basis. Replace the filter membrane according to the manufacturer's instructions.

Recommended Aquarium Maintenance Routine 

Daily, weekly, bi-weekly, and monthly maintenance tasks are part of a complete aquarium upkeep timetable.


  • Make sure everything is in good working order.

  • During feeding, keep an eye on your fish. Behavioral changes are a warning sign of potential trouble.


  • Count your fish. Smaller species can decompose rapidly in the event of fish death, producing ammonia and nitrite spikes before culminating in dangerously high nitrate levels.

Every Other Week

  • Test your water for important parameters such as pH, carbonate hardness, nitrite, and nitrate.

  • Remove any debris from the aquarium walls. Filter floss is a low-cost, highly effective solution. Scrubber or filter floss should be replaced on a regular basis.

  • The gravel should be vacuumed.

  • Perform water change of 10-15%.

  • Rinse the filters with the water that has been extracted.


  • Replace the filter inserts, cartridges, floss, carbon, and Algone. If required, clean the whole filter.

  • Examine plumbing, connections, airstones, skimmers, and other components for functioning.

  • To avoid your illumination being affected, place a glass top over the aquarium.

  • Check the expiration dates on the aquarium supplies you use. After the indicated date, do not utilize. Expired exam kits will give incorrect results and may encourage you to take action that is unnecessary.

What Size Tank Does a Goldfish Need


What Size Tank Does a Goldfish Need?

A goldfish requires a minimum tank size of 20 gallons. You'll need at least 10 gallons for each additional goldfish after the initial one. A 55-gallon tank is the ideal starting size for housing numerous goldfish.

How Long Can a Goldfish Live in a 1 Gallon Tank? 

1 gallon is simply too little for a goldfish to survive and live long in. These tanks are just too tiny for them. Goldfish do not possess a labyrinth organ, as does the betta fish. This is how betta fish can survive in such small containers. Even so, it's not ideal to keep a fish in such a cramped

Can a Goldfish Live Without a Filter or Air Pump?

Yes, goldfish can live without a filter or an air pump if necessary. Although it is not dangerous to do so, this may be a risky option. A goldfish tank with no filter will most likely have ammonia peaks. Ammonia is toxic to goldfish and can quickly kill them if the levels get too high. An air pump is not required for a goldfish tank, but it will help to oxygenate the water. This is especially important if you live in an area with hot summers.

Do Goldfish Need Heaters? 

No, goldfish do not require a heater in their tank. In fact, it is not recommended to put a heater in a goldfish tank unless the room temperature gets too cold. Goldfish are cold-water fish and thrive in water that is between 65 and 72 degrees Fahrenheit. Adding a heater to a goldfish tank may cause health problems for your fish.

Do Goldfish Sleep? 

It is not known for sure whether goldfish sleep or not. They do appear to go into a resting state at night, but it is not clear whether this is true sleep. Studies have shown that goldfish do not have the same type of sleep as humans or other mammals. They may enter a state of rest, but it is not clear whether they experience the same type of sleep cycles as we do.

What Do Goldfish Eat? 

Goldfish are omnivores and will eat both plants and animals. In the wild, their diet consists mostly of algae, small insects, and zooplankton. In captivity, their diet should consist of high-quality goldfish food, vegetables, and live or frozen foods.

What Are The Different Types Of Goldfish? 

There are many different types of goldfish. Some of the most popular include:

  • Common Goldfish: The common goldfish is the most popular type of goldfish. They are available in a variety of colors and patterns and are relatively easy to care for.

  • Fancy Goldfish: Fancy goldfish are a more ornamental type of goldfish. They come in a wide range of colors, shapes, and sizes. They are more delicate than common goldfish and require more care.

  • Comet Goldfish: Comet goldfish are similar to common goldfish in appearance. They are available in a variety of colors and are relatively easy to care for.

  • Shubunkin Goldfish: Shubunkin goldfish are a type of calico goldfish. They have a mottled pattern of black, blue, and orange. They are available in a variety of sizes and are relatively easy to care for.

  • Oranda Goldfish: Oranda goldfish are a type of fancy goldfish. They have a distinctive hood over their head that can range in color from red to black. They are available in a variety of sizes and require more care than common goldfish.

  • Ryukin Goldfish: Ryukin goldfish are a type of fancy goldfish. They have a distinctive hump on their back and are available in a variety of colors. They are available in a variety of sizes and require more care than common goldfish.

How Often Should I Change the Water in My Goldfish Tank? 

It is recommended to change the water in your goldfish tank every two weeks. This will help to prevent ammonia build-up and keep your fish healthy. A partial water change of 10-15% should be done each week. The gravel in the tank should also be vacuumed to remove any debris.


Goldfish are a popular type of pet fish that are available in a variety of colors, shapes, and sizes. They are relatively easy to care for and do not require a lot of maintenance. However, it is important to keep up with regular water changes and tank maintenance to ensure that your fish remain healthy and happy in the goldfish tank.

Poor water quality can lead to a variety of fish illnesses and, in extreme cases, death. Every aquarium is unique, and it will need its own maintenance regimen based on specific circumstances. As a starting point, consider using our aquarium maintenance instructions in this article. With a little bit of care, you can provide your goldfish with a happy and healthy home.

Sarah Robertson

I am a passionate blogger who also happens to be a fish keeping enthusiast. Writing about my hobby is something that I absolutely love to do, and it's no secret that my chosen topic is always centered around fish keeping.

Sarah Robertson

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