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Home > Goldfish > What Do Goldfish Eat? Food Options, Diet & Health Advice

What Do Goldfish Eat? Food Options, Diet & Health Advice

goldfish eating flakes

Goldfish are omnivores and should have a diet that consists of both plant and meat-based materials. That said, this fish’s digestive system is incredibly delicate, and their staple meal plan should be planned carefully. Variety is essential if you want to keep your goldfish healthy.

Many goldfish keepers think that flakes are fine as a long-term diet and will provide everything that their goldfish needs nutritionally. Unfortunately, this is why digestion and nutrient issues among pet goldish are so common. Your goldfish will not be able to grow and remain healthy if their diet is limited to one type of food.

Fortunately, there are many types of commercial goldfish foods on the market, though it may be confusing to decide which ones are worthy. Goldfish can eat flakes, pellets, gel food powders, freeze-dried foods, and cultivated live foods. This article will help you pick out the best ingredients, food types, and supplements for your goldfish.


What Do Goldfish Eat?

In the wild, goldfish will consume algae, aquatic plants, worms, insects and their larvae, and any dead fish they come across. This makes their natural diet rich in nutrients and minerals that need to be replicated in captivity. Goldfish are famously known for eating nearly any foods they are offered, and getting a goldfish to eat is usually not an issue for many keepers.

As pets, goldfish should be fed a mixture of different foods. This will not only replicate their natural diet but also keep them healthy and free of illness. Pet stores sell a variety of pre-made goldfish food that will save you from the hassle of searching for different foods on the shelves formulated for other fish. The only downside is that one type of food alone will not be enough to sustain a goldfish.

goldfish eating
Image By: oatpost, Shutterstock

Goldfish should also be fed fresh veggies and algae to aid in digestion. These types of foods can easily be prepared to give your goldfish a fibrous meal.

The main types of food offered in many pet stores are flakes, pellets, gel food powders, freeze-dried foods, or cultivated live foods. All these foods should be mixed to create variety. The ingredient labels will be helpful to determine which brands are good for your goldfish.

  • Dry foods: These are the most popular and widely distributed goldfish foods available. They include flakes and pellets. These foods should be a staple in a goldfish’s diet because they contain the most vitamins and minerals.
  • Freeze-dried foods: These can include foods like tubifex or blood worms. These make great snacks that can be fed to a goldfish a few times a week.
  • Live foods: The most common live foods for goldfish are insect larvae, crustaceans, brine shrimp, and worms. These are rich in protein and are great foods to feed spawning goldfish.
  • Frozen foods: These foods include worms, shrimp, and crustaceans. The food has to be thawed out the night before and should not be given to your goldfish when they are still frozen.

pets 6 How Much Should Goldfish Eat?

A goldfish’s stomach is approximately the size of both of its eyes combined, and this should give you context into how much a goldfish should consume. The larger the goldfish is, the more food it should be fed, though not all at once. Goldfish struggle with digestion problems because of inadequate diet and portions. Ideally, you want to split their feeding schedule into small portions of food provided throughout the day instead of one big meal once a day. You want to ensure that the food is not being wasted and left to float to the bottom of the tank. This will cause the water to foul quickly. Generally, you want to feed as much as your goldfish can eat in 1 minute without any wastage.

Many goldfish die as a result of improper feeding, diet, and/or portion sizes – which can be easily prevented by proper education.

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The more goldfish you own, the more food should be placed in the tank. Scattering the food across the waterline will ensure that each goldfish has space to eat and can get their portion of food for the day.

This also gives your goldfish time to digest their food in between meals and will ultimately help stop common digestive issues. It is important to note that goldfish should not be under or overfed, as both can have adverse negative effects on their overall health.

pearl crown goldfish
Image By: Juan Carlos Palau Díaz, Pixabay

Fact vs. Fiction

A common belief is that goldfish should fast at least once a week, but this is an untrue and dangerous misconception among the goldfish community. Goldfish should always have access to daily meals, and fasting only does more damage than good.

Important Ingredients in Commercial Goldfish Food

The ingredients lists on the backs of goldfish food containers will give you a good indication of what has quality ingredients and what is only full of fillers. This will greatly help you narrow down the foods displayed on the shelf. Most cheap goldfish food brands will use poor ingredients to fill up the weight value, and these should be avoided.

The most common filler ingredients in fish food are:

  • Wheat flour
  • Soybean meal
  • Potato protein
  • Sorbitol
  • Flaked corn

Fillers should be last on the ingredients list, as this indicates that the food contains a low number of fillers. If these ingredients are at the top of the list, it means the food is filler based and should be avoided. Fillers offer little nutritional value and are low-quality starches to bulk up the food.

goldfish in the tank
Image By: Skumer, Shutterstock

Important vitamins that should be on the label include:

  • Riboflavin
  • Zinc
  • Manganese
  • Vitamins A, B, C, D, and E
  • Niacin
  • Biotin

Basic proteins should fall into the middle of the label and include foods like:

  • Fish meal
  • Spirulina
  • Shrimp meal
  • Squid meal
  • Earthworms

Most commercial mixes will not have all the nutrients that a goldfish requires, which means you will have to purchase a few different brands to ensure that your goldfish is getting everything that it needs.


Supplements and Vitamins for Goldfish

Vitamins are rarely necessary inclusions in a goldfish’s diet. Your goldfish should be getting all its vitamins and minerals from its main diet. An excess of vitamins will not be of any use and will go to waste in a goldfish’s digestive tract. There are liquid vitamins available on the market, but these usually have no place in a healthy goldfish’s diet.

Supplements should be treated as snacks and come in the form of live or freeze-dried foods. Bloodworms are popular protein supplements for goldfish and contain valuable nutrients to help goldfish grow and develop. Protein supplements are recommended for sick or healing goldfish.

Garlic and vitamin C water supplements help to protect goldfish from minor parasites and infections. These supplements can be added to the water and replenished after a water change. They promote slime coat development, which further prevents unwanted bacteria or parasites from attaching themselves to goldfish. Another benefit is that both garlic and vitamin C are present in the water and food, which helps to boost the immune system. You can soak food overnight in garlic juice and feed it once a week to boost your goldfish’s appetite and deter parasites.

two goldfish veiltail
Image Credit: Hans, Pixabay

Dealing With Bloat and Constipation in Goldfish

Goldfish can have a variety of digestion issues if their diet is high in protein and low in plant matter and algae. Fiber is a necessary aid in digestion for goldfish and helps to combat bloat and constipation, which are associated with poor digestion.

Goldfish are not carnivores and generally need a balance between meat and plant matter in their diet. Bloat and constipation can be combatted by feeding your goldfish foods that do not overpower each other. Give your goldfish algae-based foods, and choose commercial food brands that have high plant matter on the ingredients list.

Deshelled peas work as fibrous supplements that can help your goldfish pass solid waste and clear up the digestive tract of any food that is hard to digest. Boiled romaine lettuce and spinach have the same effect.

Fasting fish is not effective in treating bloat or constipation, nor does it prevent these issues from occurring. A fasting fish will have its stomach shrink back to its original size because it is empty. As soon as you begin to feed the fish again, the stomach will expand to accommodate the meal and can put pressure on the swim bladder organs. Bloat in goldfish is an underlying issue commonly caused by food deprivation.

Is Algae a Large Portion of a Goldfish’s Diet?

Algae should not be ignored in a goldfish’s diet and has many benefits. Regularly feeding algae to your goldfish will promote normal digestion. You can feed algae through sinking algae pellets, algae-based pellets, and algae flakes. Some tanks will naturally grow patches of green algae, which can be kept for your goldfish to nibble at throughout the day. Most algae foods will be labeled for other species of fish like bottom feeders, but the formulation is safe for goldfish.

Hikari sinking algae pellets have all the algae-rich benefits that a goldfish needs, but they should not be fed daily.


Quality Commercial Goldfish Foods

These are a few of the best foods to feed to goldfish and are loved by many goldfish experts for their nutritional value.

Ideally, you should feed more than two brands of food to your goldfish. Each contains different nutritional values, and mixing them can fulfill your goldfish’s dietary needs.

feeding goldfish_New Africa_Shutterstock
Image Credit: New Africa, Shutterstock

pets 6 Plants Over Protein

Live plants can make ideal plant-based snacks for goldfish. Goldfish will easily consume a favorable aquatic plant in their tank. It is best to purchase large plants so your goldfish do not eat the whole plant in one go. Large plants will also be allowed to regrow the eaten parts.

These plants are heartedly eaten by both fancy and single-tailed goldfish:

  • Duckweed
  • Waterweeds
  • Coontail
  • Water sprite
  • Java moss
  • Wisteria
  • Anubias

Fancy and Single-Tailed Goldfish Dietary Differences

Single-tailed goldfish can have more protein in their diet because bloat is uncommon for them. Although both types of goldfish can be fed the same foods, fancy goldfish should have a diet that is limited in protein supplements. Fancy goldfish should be fed significantly less than the single-tailed varieties because their stomachs are more compact inside of their bodies. Overfeeding a fancy goldfish can cause it to have an enlarged stomach that puts pressure on its swim bladder organs and could cause swim bladder issues.

Do not bother with commercial foods that specify what type of goldfish the food is formulated for, as all goldfish have the same nutritional requirements.


Final Thoughts

Goldfish diets are more complicated than we give them credit for. It is especially important to feed quality foods to young goldfish from the start, and finding the right size pellet or flake is important. You want to ensure that your goldfish can easily chew and swallow the type of food that you are feeding them, and this will contribute to less wastage in the tank.

We hope that this article has helped you choose a suitable diet to feed your goldfish among the best brands and supplements on the market. Although a great deal of science is involved in pet goldfish diets, choosing foods can be fun! Your goldfish will be more active and healthier when they are fed the correct diet and will be immune to most disease and digestion issues. Not only will a good diet benefit their internal health, but it will also help bring out their colors and make them more vibrant.

Maintaining a strict goldfish diet regime will help them live to their full lifespan.

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Featured Image Credit: Leonardo Macedo, Shutterstock

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