Goldfish Tank – Your Guide To Successful Goldfish Care

The Goldfish is one of the most popular fish in our aquarium hobby. It may even have been the first fish you had when you first got introduced to aquariums. You may have even come across this article thinking about setting up a Goldfish tank for the first time or for a loved one. They really are amazing fish that is also easily misunderstood. Because they are usually first-time fish, a number of us enter into Goldfish care with little knowledge on what is needed to have them thrive.

I’m sharing this article with you today so you can learn all the essentials plus more. I want you to be very successful in caring for your pet Goldfish. As quick disclosure, this blog post will contain affiliate links which I may get a small commission at no extra cost to you should you make a purchase. Now let’s get started!

Key Takeaways

  • Goldfish are not beginner fish. They require larger tanks and are quite messy
  • They are coldwater fish and are best with other goldfish
  • Live plants with goldfish is possible if you know what plants to select
  • There are slim-bodied and fancy goldfish. Slim bodied are more athletic and can live in ponds

History of Goldfish

One crazy fact about Goldfish is that they were first kept for their meat. Yes, that’s right. Goldfish used to be what was for dinner in China, their area of origin. Goldfish are the domesticated version of wild carp from East Asia. Their original colors were silver-grey and they were known as “chi” in the East. It was one of the most common staples of meat in China at one time.

Common Carp

As carp continued to be bred for meat, a strange thing happened. Genetic mutations would occur with the carp and these “mutants” would end up with flashy red, yellow, and orange colors. If these fish were in the wild, they would get quickly eaten by predators since they stood out so much. These flashy-looking new fish caught the eye of Buddhist monks in the 9th century. They began to keep these colorful fish in their ponds. The Goldfish was born at this time as an ornamental pet. 

The breeding of the fancy Goldfish varieties did not begin until the 1600s starting in Ming Dynasty China. They were highly regarded for their scales and it was tradition for a man to give his wife a goldfish on their first anniversary to symbolize the prosperous years to come. Goldfish were imported to North America around the 1850s. This video by Aquatography provides a deep look into the origins of goldfish.

Care – The Major Factors We Need To Know

Goldfish on the surface seem very hardy and easy to take care of. For the most part, they are. However, we want to have the best environment we can place them in. I want to go beyond the basic beginner setup and set you up for long-term success. Goldfish care can be broken down into several parts:

We have a video from our YouTube Channel that you can follow along as well. Be sure to check both as our blog goes into more detail. If you enjoy our channel, be sure to subscribe as we post videos every week!

Aquarium Size

I’m going to say it upfront to my readers. Goldfish do not belong in a Goldfish bowl. You may see Goldfish bowls everywhere, but bowls are not big enough for the long-term. You may purchase them as young new fish for your fish tank, but they will get large. In fact, the Common Goldfish can grow up to 10 inches in size and Fancy Goldfish can grow up to 8 inches in length. Some have grown as large as cats in rivers! That is a lot of Goldfish for a tank! Goldfish also have a lot of mass, especially the Fancy types. Given their adult sizes, it’s no wonder they were originally kept in ponds.

When sizing an aquarium for a Fancy Goldfish, you will want to start out with a tank size of 20 gallons for a single Fancy. After that, it’s roughly 10 gallons per every other Fancy Goldfish. This means a 40 gallon tank can hold 3 adult-sized Fancy Goldfish. That doesn’t sound like a lot of fish, but remember they get pretty big. We need to ensure an aquarium is big enough not only for them to have room to swim around, but also so you are not a slave to water changes.

For a common variety of Goldfish like a Comet, you will want to consider an aquarium size of 30 gallons and target at least 4 feet in length. Each subsequent comet you add would need an additional 12 gallons so for a 55 gallon tank, we are talking about 3 full-size Comets. Again, not a lot of fish. Keep in mind that Comets can grow up to 12 inches in length!

For a Fancy Goldfish setup, I would recommend a larger aquarium like a 55-gallon tank or 60 gallon breeder.  These 4-foot-long tanks offer everything you need to get started. You can go cheaper if you wait for a dollar-per-gallon sale at your local chain pet store to pick these aquariums up.

Filtration

Goldfish in general are very hard on the bioload of an aquarium. They are large, messy, eat constantly throughout the day, and stir up your Aquarium Substrate all day. Maintaining a Goldfish tank requires a hefty filter. Keeping in mind that Goldfish are usually an entry-level fish for Aquarists, we are going to focus on more budget-friendly options. Our best option is a good quality aquarium Power Filter like a Hagen Aquaclear

The Hagen Aquaclear is a quality-made, readily available power filter that has stood the test of time. It is very easy to customize each section of the filter stages to suit your needs. It will provide years of reliable operation. Make sure you size up one model that is made for a larger aquarium. A goldfish aquarium tends to produce a lot of waste, so get try aiming for oversized filtration

Parameters (Water Quality)

The main thing with Goldfish tanks once you have the tank cycled is consistently monitoring your Nitrate and pH levels. Ammonia is generally a concern when you first cycle the tank or when you add new fish. Goldfish, due to their messiness and consistent desire to eat will produce a lot of waste. A full goldfish tank will usually end up running higher nitrate levels as a result. You want to test your nitrate levels regularly with a proper Aquarium Test Kit. Take care of your goldfish by ensuring your nitrates don’t go above 40. This will ensure you have the best water quality possible. 

The pH levels of your Goldfish aquarium are also critical. Goldfish are like an aquarium at 7-8 pH at all times. This is different from most tropical fish and planted aquarium environments which prefer a pH at an acidic level lower than 7. Make sure your tap water has the proper pH and adjust accordingly if your tap is below 7. Always use a water conditioner like Sea Chem Prime to treat your water. A water conditioner will remove harmful chemicals out of your tap water like ammonia and chlorine and make it aquarium safe.

Temperature

Goldfish are cold water fish. Anything over 75 degrees for a Goldfish is going to stress out your fish. Goldfish actually have a large range of temperatures that they can live in. The range is generally from 50-75 degrees F, with the general ideal range being 65-72 degrees. This means that if you keep your home at room temperature, you should be fine without having an Aquarium Heater in your tank.

There are two things we have to keep in mind with Goldfish tanks. If you live in a hotter climate, you may need to control the temperature in your aquarium in the summer. This may require an Aquarium Chiller or getting your specific room where your tank is to a cooler temperature with a mobile AC. If you live in a cold climate with very cold winters, you may want to consider having a heater handy when the temperatures get below freezing in your area. 

Decorations

When we think about Decorations for a Goldfish tank, we have to consider both space and safety. Common Goldfish are fast and enjoy swimming around. Fancy Goldfish are slow, clumsy, and have delicate fins. Both types of Goldfish need their space to swim. Consider having an open aquascape when building out a Goldfish tank.

When it comes to the decor itself, we want to consider rocks, and artificial plants without sharp edges. We take the same consideration as we do with Betta Fish where we avoid sharp edges as the long fins of our Fancy Goldfish can get caught and damaged.

A good brand to look into is marina naturals when looking at silk artificial plants. These plants will not damage the fins of your Fancy Goldfish. You will need to keep in mind that goldfish like to dig out plants. It may be a good ideal to anchor these down with rocks.

Substrate

Goldfish love to stir the substrate in search of food. They have big mouths, so substrates that are medium or larger in size can pose a problem for them as they can accidentally shallow the pebbles. We want to make sure that goldfish have a substrate that they can easily stir and scavenge around. Knowing this, the best goldfish tank substrate is going to be a sandy one. 

A sandy grain size substrate like the one sold by Caribsea is what we are looking for. We want to work with a thin layer of sand. This is to counteract the big pitfalls of a sandy substrate. Sand can compact and create anaerobic pockets, which can be very dangerous for your fish. A thin layer that barely covers the bottom of your aquarium and no more than 1/2 an inch is what we are shooting for. This sandy substrate will get stirred all day by your Goldfish and mimics their natural environment. This substrate is also pH neutral – a major factor because Goldfish need a pH of 7.2 – 7.6.

Diet

Food for Goldfish is an interesting topic because the industry is loaded with a lot of food targeted at beginners. These foods are cheap, easy to feed, clean, and last a long time. That is great for us humans, but they are not that great for our Goldfish.

The most basic food offered to Goldfish is flakes. Most flake food offered on the market is full of fillers, which long-term can be unhealthy for your Goldfish and creates a lot of waste. We want to upgrade the diet of our Goldfish to something better. At a minimum, we want to think about quality pellet food.

A good brand for goldfish pellet is Northfin. They sell a premium Goldfish pellet formula specially designed for them. It is free from fillers and includes a healthy dose of Omega 3s to really help bring out the color in your Goldfish. I would recommend presoaking your pellets in aquarium water before you feed them to your Goldfish. This will allow for the pellets to soften and expand a bit so they don’t expand in your Goldfish’s gut. 

Going further, we can look into freeze-dried food. I would recommend Hikari’s Bio-Pure Krill. Kill has the ability to boost carotene levels in your Goldfish. This helps produce better coloration in your Goldfish and can prevent them from turning black. This formula is multi-vitamin enriched so you do not have to supplement with a vitamin supplement like Vita-Boost.

The next step up would be frozen food. These you would likely need to purchase from your local pet or fish store. For frozen food, look for brine shrimp, blood worms, or daphnia. Good brands to look at would be Hikari or Cobalt Aquatics.

Lastly, we go with live foods. For live foods, I want to look at live plants. Goldfish in general, are known for eating a number of aquarium plants. While this can be bad if you are looking for a planted goldfish tank (it is possible to have plants with goldfish – more on this later), we can use this to our advantage when supplementing our Goldfish’s diet. One plant that Goldfish love to eat that is fast-growing and readily available in our trade is Duckweed.

If you are part of an Aquarium society or know anyone with a Planted Tank, there is a good chance they either have Duckweed or have grown it in the past. Duckweed is also grown in ponds for Koi and Goldfish. Goldfish love to gobble this plant up. It is very cheap to obtain and a very fast grower. It is very important to have food readily available in your aquarium for a Goldfish. We have to keep in mind that Goldfish do not have true stomachs.

Because of this, they are always eating and hungry. You do need to feed goldfish regularly, but a natural food like Duckweed can really come in handy because you can make it available in your tank, it’s a natural filter, and it can be eaten away by your Goldfish throughout the day.

Aquarium Mates

Tank mates for Goldfish can be quite tricky. They have several factors working against potential Goldfish tank mates. They are a coldwater fish, so that eliminates all tropical freshwater fish right off the bat. Fancy Goldfish also are slow and have large fins, which can be attractive to nip for a more active fish. Goldfish can also be bullies themselves. Their large size, mouths, and mass can present problems to smaller fish. For this reason, the best recommendation is to have a Goldfish-only tank.

That being said, there are some tank mates that would work. These tank mates would be:

  • Coldwater snails like Nitrite and Apple Snails
  • Brittle Nose Plecos
  • Dojo Loaches

Snails are a great addition because they will work on algae in the tank and for the most part Goldfish should leave them alone. If the Goldfish do decide to harass them, they are large enough to handle themselves and give you enough time to reconsider their compatibility. Every Goldfish is different after all.

When it comes to Plecos, only the Bristle Nose Pleco is compatible with a goldfish. Common plecos are generally a bad idea as they require driftwood and can get very large.

Dojo Loach

Dojo Loaches (pictured above) are likely the best candidate when it comes to other fish in a goldfish tank. They get rather long at 5 inches and require at least a 30-gallon tank, but they can tolerate the cooler waters of a goldfish tank. They are very peaceful, very active, full of personality, and excellent scavengers. 

It’s always best to introduce these new fish and inverts AFTER our goldfish have been added. We want to make sure our goldfish are established since they tend to be the ones that are bullied not the other way around! You will also want to consider a larger tank if you want to have other tank mates. A 55 gallon or 75 gallon fish tank would be good options.

Live Plants

Goldfish Planted Tank

Plants for Goldfish like tank mates are tricky. You have a number of things working against you when it comes to them. Because Goldfish like cold water that is 7-8 in pH, this eliminates the majority of tropical aquarium plants available for sale. Goldfish also love to gobble up plants. They will eat just about any plant you stick in the tank. Another factor is that Goldfish stir up the substrate, which means that if you have any rooted plants that need to be established in your substrate, it is likely that your Goldfish will dig them out.

That seems like there are a lot of things going against you when it comes to aquarium plants, but we also need to think about the benefits as well. Plants will really help with your water change efforts. They will thrive in the high nutrient environment that goldfish will create with the waste they produce. If you don’t want to be a slave to water changes, live plants can be your ticket to relief. In large quantities, they can act as natural filtration for your tank.

So let’s talk about what plants work best. We want to make sure these plants tolerate higher pH, will do well with high nutrients, won’t mind the cooler temperatures, and won’t get eaten by our Goldfish. These are:

All of the plants above are considered Low Light Aquarium Plants. All you need to do if you want aquarium plants is to upgrade your lights to a proper Planted Tank LED System.

Types

There are a lot of different Goldfish types to house in your aquarium. All goldfish are long-lived and will provide years of joy for you. I’m going to break down a small list of Goldfish for you. I’m going to split it into two types:

  • Slim Bodied Goldfish
  • Fancy Goldfish

Slim Bodied

Slim bodied Goldfish are one of the hardiest fish you can purchase in the hobby. They can be placed in home aquariums or outdoor in ponds. They will tolerate a wide range of temperatures. They are fast swimmers, very active, and aggressive eaters. They cannot be kept with Fancy Goldfish as they will out-compete them in an aquarium with how fast they swim around and eat. Below are a few types of slim bodied Goldfish:

  • Common Goldfish
  • Comet Goldfish 
  • Shubunkin Goldfish 
  • Wakin Goldfish

The common Goldfish is also known as your “feeder” goldfish at pet stores. They are also the Goldfish you used to get at fairs as prizes. This Goldfish most resembles their original ancestors, the carp. They can grow as long as a foot if given a large enough aquarium or if housed in a pond. They are very hardy, very cheap, and long-lived fish.

The Comet Goldfish is a variant of the common Goldfish that has a long fancy tail. They share the same hardy characteristics of the common, but with more flash with their tails. They will also get a foot long and are fast swimmers. They a relatively cheap fish to purchase.

The Shubunkin Goldfish is a multicolored goldfish. These you will usually see placed in ponds as they get long and command a higher price tag than the former 2 mentioned. Some varieties of Shubunkin will grow fancy tails and fins.

Shubunkin Goldfish

Fancy

Fancy Goldfish are selectively bred fish that have been created over the years. They are not found in the wild and exhibit multiple unique characteristics depending on the type. They are fish with a lot of mass on them and are generally clumsy in nature. They have long elegant fins and are generally slow swimmers. Because of the slower swimming speed, they do not mix well with slim-bodied Goldfish as they will be unable to compete with them for food.

These egg shaped fish are valued for their looks. They tend to be more delicate than slim bodied Goldfish, but there are several varieties that are hardy and appropriate for beginners. A few examples of Fancy Goldfish types are:

Ryukin Goldfish

The Fantail, Black Moor, and Ryukin Goldfish are great fancy varieties that are appropriate for beginners. The Lionhead and Telescope Goldfish are varieties that would be considered more delicate and better suited for experienced Goldfish keepers. The main difference between the first three and their others is what stands out with the two other fish. The Lionheads are so modified that their dorsal fin is missing. Their fleshy-like head and clumsy nature make them sensitive to injury. For the Telescope, it’s the eyes. The eyes give them limited vision and make them delicate. It’s another Fancy that is not for beginners.

I go into more detail on fancies in this blog post, but I wanted to help you identify what is a hardy Fancy Goldfish and which ones aren’t. The less modified features of the fish, the more likely it will be better suited for a beginner. Of all the Fancies listed here, my personal favorite is the Ryukin. It is bold, elegant, and hardy. It is a wonderful addition to a Fancy Goldfish aquarium.

Putting It Together

We have discussed a lot about Goldfish Tank care, food, housing, and types of Goldfish. It’s time to put everything we have learned today and make a comprehensive setup. In this setup, we are going to set up a Goldfish tank with live plants. You can opt not to use plants and save yourself on upgrading your light.  

  • Tank – 55 gallon for 60-gallon breeder
  • Lighting – Add another light strip to host low-light plants
  • Filter – Hagen Aquaclear or Fluval Canister Filter
  • Heater – None
  • Plants – Java Fern and Anubias
  • Rocks – Margo Garden Products 3-5″ Rain Forest Large Rocks (available on Amazon)
  • Substrate – Caribsea Super Naturals
  • Fancy Goldfish – 2 of your choice (after the tank has been cycled)
  • Water Conditioner (To treat tap water) – SeaChem Prime

To save on money, we can purchase a 40 gallon breeder to 55 gallon tank during Petco’s dollar-per-gallon sale. All the other components fit very well for this setup and for what we want to house. If you opt for a 55 gallon tank, you can house 3-5 fancy goldfish. You will want to anchor your plants to your rocks so they don’t get stirred up by your Goldfish.

If you opt for a dollar-per-gallon sale tank, you are free to select the light of your choice. I would recommend an led light like the Serene Pro LED if you are selecting a light for a planted aquarium setup.

Additional Resources

There are many books out there that go beyond the scope of this blog post. However, not all are created equal. There is one book I recommend when it comes to Goldfish care.

Fancy Goldfish: Complete Guide To Care And Collecting 

Over 100 Photos!
Fancy Goldfish: A Complete Guide

An in-depth book on the world of fancy goldfish. Highly recommended and full of timeless knowledge

Buy On Amazon

This Book Written by Dr. Johnson goes over diseases, prevention, health, breeding, and proper fish selection. It contains over 100 color photos of Fancy Goldfish. The information contained in this book is a full deep dive into the world of Fancy Goldfish. You will become an expert in knowledge after you read this book. It does have some outdated information given it was published back in 2001, but the majority of the information in this book I would consider evergreen.

I would highly recommend it to anyone who really wants to keep the more exotic Fancy Goldfish or considering expanding into larger display tanks.

FAQs

What Size Aquarium Do They Need?

The minimum size tank that a goldfish needs is 20 gallons. For each additional goldfish after the initial one, you will need at least 10 gallons. The best starter size to house multiple goldfish would be a 55 gallon tank.

How Long Can They Live In A 1 Gallon Aquarium?

A goldfish will not thrive and may not live very long in a 1-gallon tank. These tanks are too small for them. Goldfish do not have a labyrinth organ like a betta fish. This is how betta fish can live in small containers. Even then, it’s not ideal to place a fish in such a small tank. Consider placing your goldfish in an appropriately sized tank for its long-term health.

Can They Live Without A Filter Or Air Pump

Yes, goldfish can live without a filter or an air pump. However, it’s risky to do so. Without a filter, a goldfish tank may experience ammonia spikes.

Closing Thoughts

Goldfish go way beyond the fish in the bowl that money of us have seen in the past. There are many varieties of Goldfish with some of the exotic Fancy types selling for hundreds of dollars. They are large fish with personality and unique aesthetics. They do require larger tanks long-term, but they are long-live fish easily living over 10 years in more aquariums. I hope I showed you what Goldfish can offer you as a pet by reading this post. If you have any questions, leave a comment below. Thank you for reading.

2 COMMENTS

  1. I have an issue with my tank. It is very cloudy but all my levels are great and in the proper scale that they should be in. I change the water every Monday or Sunday i check to make sure. I have one sponge filter and an over the rim filter. It’s a 36 Gallon tank. It very very cloudy and i have no idea how to cure it. I just recently added another sponge filter and I’m at a loss at what to do.

    Reply
    • Hi Carly,

      You might want to consider upgrading to better filter unit like a power or canister filter. Carbon will help out with the cloudiness and the added biological media will keep the cloudy water in check. Just make sure you work in your new filters if you do that. You don’t want to remove your sponge filter immediately once you get the new filters. you can either stick the sponge filter in the new filter or give your new filter a month to establish before removing the sponge filters.

      Reply

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