Goldfish are one of the most commonly stocked fish breeds in the world. Goldfish are the descendants of Chinese carp and were first “domesticated” in China over 1,000 years ago. Today, you can find goldfish in homes, classrooms and offices all around the globe. However, many people have questions about feeding their goldfish: How often do you feed goldfish? What to feed goldfish? How much to feed goldfish?
If this is you, you're in luck! In this article we’ll cover everything you need to know about feeding your goldfish. From the type of food they most enjoy, the best feeding times and routines, and additional dietary supplements and food sources you might want to consider. This article will provide you with everything you need to keep your goldfish happy and healthy for many years to come!
First, let's clear up a common misconception. Many people mistakenly think that goldfish are a hardy and tough fish that can take tons of neglect and abuse. Including things like a dirty tank or an irregular feeding schedule. However, nothing could be further from the truth.
Goldfish don’t thrive on neglect or inconsistent care – and neither does any other kind of fish! In fact, goldfish have very particular needs when they’re in a captive environment, whether that’s a tank or a pond. To do well in a domestic aquarium they need clean water, a sparkling clean tank, and plenty of other essentials. And of course food plays a major role as well, which is probably why you're here.
How often to feed goldfish, what to feed goldfish, and how much to feed goldfish is an essential part of your goldfish feeding routine.
Four fun goldfish feeding facts
Did you know that goldfish don’t have a stomach? Or that they actually have teeth? It’s true! Your seemingly “ordinary” little goldfish is actually quite an extraordinary animal. In this section we’ll cover some of the anatomical curiosities that make goldfish special and that you need to know to understand how to feed them.
Goldfish have teeth
Goldfish have a set of teeth hidden away at the back of their throat. The teeth in their throat are called “pharyngeal teeth” as they are located in the pharynx, which is just behind the nasal cavity and mouth, and right above the esophagus. They’re not “biting” teeth – instead, goldfish use them to help crush their food.
Goldfish have a special kind of jaw to help them feed
Goldfish also have something called a “protractile jaw”, which is a jawbone that can be pushed forward while they’re feeding. You’ll see them using this when they’re foraging through the gravel or substrate at the bottom of your tank looking for food. Goldfish use their jaw to help bring the gravel and/or food into their mouth, and then spit the gravel out again after they’ve sieved out the food.
Goldfish don’t have tongues
Your goldfish doesn’t have a tongue, just a gullet. So how do they taste their food? Goldfish have taste buds distributed all over the inside of their mouths, as well as around their lips on the outside. Goldfish sample potential food items by biting them to see whether it is food or not. You see this in action when they are sifting through the gravel at the bottom of their tank. Goldfish will take some gravel into their mouth along with a tidbit of food, and then spit the gravel back out.
Goldfish don’t have stomachs
Perhaps the most unexpected of all their anatomical features is the fact that goldfish don’t have any kind of stomach. So how do they digest their food?
Goldfish break down and absorb their food as it moves through different parts of their intestinal tract, which is twice the length of their body. This curious anatomical fact is one of the reasons that goldfish process their food so quickly – and also the reason they produce a lot of waste!
Their fast digestive process means that toxins and waste products will build up in a goldfish tank very quickly. This is one of the primary reasons that you need to keep your goldfish tank sparkling clean. The use of high-quality filters in your goldfish tank is highly recommended as well.
The fact that they don't have stomachs also has an important bearing on what you can feed your goldfish and how often you should feed your goldfish.
Feeding fancy goldfish can be especially difficult. The shape of their body and the position of their internal organs can cause even more trouble for digestion than your garden-variety standard goldfish.
Because a goldfish’s digestive system moves quickly, they need to absorb their nutrients fast.
Soft food works better for feeding goldfish than hard food because it is easier to chew and takes less time to be digested.
You’ll also need to make sure you feed your goldfish more than once a day or they’ll go hungry. A few smaller meals each day is the best method for feeding your goldfish. However, goldfish are also notorious over-eaters. Be sure not to feed them too much or they can bloat, get sick, and even die.
Feeding goldfish is trickier than you might have thought, right? There’s a lot to be mindful of when it comes to goldfish keeping.
What do goldfish eat in the wild?
Goldfish are true omnivores, meaning that they eat both protein and vegetable matter. In the wild, goldfish will eat a wide range of food sources depending on what’s available. This includes insects and their larva, plants, worms, shrimp, various other crustaceans, and sometimes even other small fish. Goldfish are greedy and will basically eat anything they can swallow.
Goldfish are primarily foragers rather than hunters. They’re better at rooting around at the bottom of the ponds, lakes, or rivers that they live in. Like their ancestors the common carp, goldfish sift through gravel, silt, and sand for tasty bits and pieces of food. They have very sensitive mouths that help them find food. In addition, they will also nibble on plants for added nutrition and fiber.
Like all animals, goldfish do well on a diet that closely mimics what they would eat in their natural environment.
If you’re keeping goldfish, it can be a good idea to try to recreate this kind of environment for your pets.
What to feed goldfish: commercial or fresh food?
Here’s a question that creates some robust discussion among goldfish owners. What can you feed goldfish? Should you feed goldfish commercial food, like flakes or pellets, or give them a varied diet of fresh ingredients instead?
Goldfish flakes have to be one of the most commonly recognized fish food products on the market. If you had a goldfish when you were little, you probably fed it with goldfish flakes – unless your parents were experienced aquarists!
Quick and easy, this method of feeding is almost synonymous with goldfish ownership. It ranks up there along with the idea that goldfish can live happily in a round bowl (They can’t! Check our previous article for more details).
However, many enthusiasts agree that flakes or pellets, while a good food source for goldfish, shouldn’t be the only one. If you decide to feed your goldfish primarily flakes or pellets, we recommend that you supplement your goldfish’s diet with additional fiber and nutrients from fresh vegetables or fruits (discussed below).
Flakes and pellets often have additives and filler
Commercial fish food products can be a little like junk food for your fish. Sure, they’re quick and easy – like a burger and fries – but just like fast food, they’re not the most nutritious options you can offer your fish either. Although the labels will often say that flakes or pellets are a “complete goldfish food” this isn’t usually the whole story.
While these foods may be specially formulated to meet all the nutritional needs of your goldfish, they are less likely to meet all their dietary needs. These are two different things.
The biggest factor here is the carbohydrate content of dry food. Commercial goldfish flakes and pellets are often “padded out” with bulking agents and carbohydrates. They also require extra processing and additives.
A goldfish who lives solely on commercial food may have trouble with their digestion or become constipated, just like you would if you didn’t eat any fiber in your diet. Additional fiber in the form of vegetable material or fruit will help keep your goldfish healthy.
Other Issues Flakes and pellets can cause for your fish and tank
There are some other issues you should be aware of when it comes to feeding goldfish dry food.
In their natural habitat, goldfish pick up their food from the bottom or the mid level of their habitat. Goldfish spend a lot of time sifting the substrate to pick up scraps of food.
When they’re fed flakes, which float at the water surface, some goldfish can tend to gulp air at the same time. This is thought to cause swim bladder issues. Some other issues to be aware of include:
- Fish flakes will start to break apart and decompose as soon as they touch the water. This can cloud the water and add to the pollution levels in your tank.
- Flakes start to lose their nutritional value once their packaging is opened. When they are exposed to the air they'll also absorb moisture and become damp.
- Pellets can sink to the bottom, where they will start to rot if your goldfish don't find them soon enough.
- When pellets absorb water they can expand to two or three times their original size in your fish’s stomach. This can cause bloating and constipation for your poor fish. If you absolutely must use pellet food it’s a good rule of thumb to always soak the pellet in some tank water first.
For all of these reasons, we don't recommend a diet of dry food alone. However, you might use flakes or pellets as a basis for their diet and then add additional vegetable material or live food options as treats.
Flakes and pellets can also be useful to have in the cupboard for emergencies, or if you’re going away overnight or through a weekend. Check our article here for lots more information about feeding your fish while you’re away on vacation.
Pellets have the advantage that they’re easier to measure out accurately for beginners or stand-in feeders while you’re away, and they have a longer shelf life once they’re opened, too.
The Best Dry Food options for Feeding your goldfish
If you do choose to purchase some dry food for your goldfish, here are our three top picks from Amazon:
TetraFin Balanced Diet Goldfish Flake Food
These flakes are designed to provide a nutritionally balanced diet especially for goldfish, including vitamins, minerals and trace elements. They contain high-protein fish meal as a core ingredient. They are specifically designed to stay firm and not cloud your tank water.
-
Aqueon Goldfish Granules
These granules are made using only natural ingredients and will provide your goldfish with a diet that meets their nutritional needs. Suitable for common goldfish, fancy orandas or koi. They are specially formulated so that the fish utilize more of what they eat, creating less waste.
Hikari Lionhead Sinking Pellets
These premium pellets are specially designed to sink in your tank, meaning your fish can scavenge for them naturally and avoid any potential for air-gulping. While more expensive than your typical pellet, they are specially formatted to promote the vivid colors and features of fancy goldfish, including Lionhead, Orinda, Ranchu and Azumanishiki. Don't just take our word for it, read the reviews on Amazon.
Another option to feed your goldfish: Gel food
Gel food is an alternative food preparation that you can use to supplement your goldfish’s diet, or use as a more primary source of food. Gel food usually doesn’t contain any bulking agents or artificial additives, so it can be a good alternative to flakes or pellets. You can even make your own gel food at home – check this article for some recipes or pick up one of the many books on the topic you can find on Amazon.
Gel food is simple to prepare using a setting agent like gelatin or agar agar. You can include the protein-based ingredients that your goldfish loves when making your own gel food. You can also add extra items such as red bell pepper to help improve your goldfish’s color, as well as spirulina, or other vegetables for additional fiber.
You can buy pre-made gel food from your pet store or online. Here's our top pick for gel food from Amazon:
Repashy Super Gold
This is a meal replacement gel that is specially designed for goldfish nutrition and digestion. To feed it to your goldfish you mix it with water and heat it in the microwave. Once it is done you let it cool at room temperature. Once cooled, you cut it into cubes or shred it into tiny pieces. It will keep in the fridge for 2 weeks, or the freezer for 6 months.
Feeding Your Goldfish A balanced diet of fresh foods
Because goldfish are omnivores, they will also benefit from a varied diet of fresh foods. Fresh foods are rich in nutrients and can help with digestion. This means they need to eat both protein and vegetable matter. Fresh foods are also a good choice when you're wondering what to feed your goldfish when you're out of packaged food.
Goldfish rely on protein, vitamins and minerals to help build muscle, provide essential nutrients, and support their immune system. They also rely on natural fibers to help keep things moving along their digestive tract.
There is a long list of “human” food that you can feed your goldfish. While they make great food for your goldfish, they should be supplementary items and not their primary food source. Some of the items that are high in fiber include:
Feeding Goldfish Vegetables
Here's a video on how (and how not) to feed your goldfish peas. Obviously do not put aluminum foil in the microwave like this person did...
In general, you should blanch or lightly boil vegetables before you feed them to your goldfish. Boiling helps to break down some of the cellulosic fibers that can be hard to digest. Boiling or blanching also makes the food softer, meaning that your goldfish can get it into their mouths more easily.
Remember to feed very tiny chunks of these foods – one or two millimeters in diameter is plenty big enough – something about as big as your goldfish’s eye. Your goldfish does not have a stomach, so it has to grind these tiny pieces using its pharyngeal teeth.
With spinach and lettuce, you can tear a leaf into smaller pieces. Or another option is to clip a leaf to the side of the tank to make it easier for your goldfish to grab and tear little pieces off. If your fish tend to suffer with swim bladder problems or constipation/digestive issues, additional fiber in the form of spinach or lettuce can be very helpful.
You can also plant your tank with live plants that your goldfish will find attractive to nibble on. They love to eat plants – especially duckweed - so it’s a good idea to have a few different types in your tank. Having multiple plants will reduce the strain on any one plant from your goldfish nibbling on it.
You can also add some different plants for short periods from time to time as a special treat, such as anacharis.
Feeding Goldfish Fruit
You can feed your goldfish tiny amounts of fruit including:
You should think of fruit as a treat though, rather than a regular or daily food item. It’s high in fructose, a kind of sugar, which your goldfish aren’t used to digesting.
What live food can you feed your goldfish?
Goldfish will benefit from live food that is similar to what they would eat in their natural environment. These foods include:
Do be aware that if you decide to feed live food to your goldfish, there is a very small possibility that your goldfish can catch a disease or parasites from these items.
A good way to avoid this possibility is to feed your fish frozen or freeze-dried versions. They won’t be as close to the “real life” situation you’re aiming to replicate, but they significantly reduce any risk of disease transmission. Frozen food often comes in small blister packs. You just pop out the food, thaw it, and feed it directly to your goldfish. Freeze-dried foods have a long shelf-life and they can be quicker to rehydrate and feed to your goldfish. Here are our top-rated freeze-dried goldfish food on Amazon:
Hikari Freeze-dried Bloodworms
A pharmaceutical-grade freeze-drying technique ensures these bloodworms are as close to fresh as possible and are free of any parasites or harmful bacteria. They also won’t cloud your tank water. You can feed these to your goldfish as a treat or as part of their regular diet. You fish will love them!
Hikari Freeze-dried Tubifex Worms
The same pharmaceutical-grade freeze-drying technique is used for all Hikari products so these are also as close to fresh as possible while also parasite free. You can feed these to your goldfish as they are, or soak them in a cup of aquarium water first to soften them up and expand them before your fish consumes them. Your fish will love tearing one of these cubes apart.
San Francisco Bay Freeze-Dried Brine Shrimp
Specially raised in enriched saltwater ponds, the shrimp are chock full of essential fatty acids, protein, and pigments that can help give your goldfish a rich and vibrant color. These solid cubes of shrimp can be crumbled to a powder or broken into smaller chunks before you add them to your aquarium.
What you should not feed your goldfish
We've all been there... You're out of goldfish food, your pantry is bare, and your goldfish are hungry... Can you feed your goldfish bread? Can you feed your goldfish leftover meat? Some improvisation can help in this situation, but be aware that there are some foods you should never give to your goldfish, including:
- Avoid vegetables that have bitter flavors (e.g. cabbage, brussel sprouts, broccoli, etc.)
- Any type of onions, leeks, or shallots
- Bread is a big NO NO! (These carbohydrates are hard for your goldfish to digest)
- Anything that isn’t part of their natural diet (cookie crumbs, anything with added sugars, sweets, anything salty, anything with dairy, etc.)
- Any type of meat
How often do you feed goldfish?
Goldfish can be little gluttons. They're known to beg their owners for food – waggling their little fins and bobbing at the surface. They’re so food-responsive that you can even train them to come to the surface and take food from your fingertips!
Have a look at this video on how to hand-feed your goldfish.
Goldfish get hungry fast because they don't have a stomach. However, you must be very careful not to overfeed your goldfish. Overfeeding can lead to serious problems such as bloat, indigestion, or even death. So how many times a day should you feed your goldfish? A good rule of thumb is that you should feed your goldfish twice a day.
If you're feeding your goldfish 3-4 times a day make sure each feeding is relatively small.
Another way to think about how much to feed your goldfish is that the amount of food should only be the size of your goldfish’s eye.
After feeding time is up scoop out any leftover food so that it doesn’t begin to decompose inside your aquarium. This will also help prevent your greedy goldfish from gobbling too much.
Your goldfish might still act hungry and beg you for food after feeding time is over but don’t give in! Goldfish are the Labrador dogs of the aquatic world – they will happily eat themselves to death if given the chance.
How long can goldfish live without food?
Goldfish can generally go without food for up to around eight days, but sometimes they can last as long as two weeks. Two goldfish did once survive 134 days without food after an earthquake in New Zealand – but please don’t try to beat this record…
In general, leaving a goldfish without food for eight days isn’t a very responsible way to take care of your fish. If your fish doesn't have a regular supply of food, it will need to metabolize nutrition from its muscle stores. This will have a wasting effect on your goldfish.
Another factor to consider is that even if your fish survives for eight days without food, they still need their water to be kept clean.
Spiking ammonia levels in your tank will kill your goldfish faster than going without food.
Not feeding your goldfish while you're on vacation is also not a very nice thing to do. Would you like to go without food for eight days? No! And neither does your goldfish.
How to feed your goldfish while on vacation
There are plenty of ways to feed your goldfish while you’re on vacation. These include:
Fish feeder blocks
These are an inexpensive and easy to use. However, they can make your tank cloudy! Also, some of them contain copper, which can be toxic to invertebrates. We are not a big fan of feeder blocks
Automatic fish feeders
Automatic feeders, besides a house sitter, are the best option for keeping your goldfish fed while on vacation. They are simple to use - you just fill them with fish flakes or pellet and program them to drop the food into the tank at the right time(s) each day. This is our top-pick for an automatic fish feeder on Amazon.
House Sitters
Getting a house sitter to look after your goldfish aquarium while you're away is the best way to ensure that your goldfish are being fed and your tank is staying as clean as it needs to be.
Check out our previous article here for more tips and tricks for caring for your goldfish while you’re away from home.
Conclusion
As you can see, there are a lot of factors to consider when it comes to feeding goldfish.
Your goldfish needs a balanced diet with a lot of variety in order to get both the nutritional and dietary requirements it needs to live a long and healthy life.
While commercial foods can provide a good basis, it is a good idea to supplement your goldfish’s diet with other foods such as frozen or freeze-dried food, live food, and ample vegetable material a few times a week.
What’s your experience been? Have you found the perfect recipe for goldfish feeding? Tell us in the comments!