Feeding Your Aquarium Fish the Right Type of Food (2024)

Freshwater Aquarium Basics

Keep Your Fish Healthy Through Proper Nutrition

Shirlie Sharpe

Shirlie Sharpe is an aquatic expert and writer with over three decades of experience keeping and raising ornamental fish. She has consulted with The Minnesota Zoo and the National Aquarium. Shirlie has also authored a book on setting up aquariums.

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Updated on 10/12/21

Choosing the Right Food

The fish food section at the pet store can be overwhelming to a novice owner. First, learn more about your fish species, starting with whether the species are meat-eaters (carnivores) or vegetation eaters (herbivores). From there, options to choose from include:

Dry Food: When you think of fish food, you think of flakes. That's the most common option for feeding a tankful of fish, but dry fish food also comes in granules and pellets, sinking, and floating varieties, as well as options for specific species. Dry fish food can be lower in fiber, but adding vegetable foods to the diet will help reduce the risk of swim bladder disorders and bloating for vegetarian species. Pet stores may also sell sheets of dried spirulina or nori algae, which are great for herbivorous fish to nibble on.
Frozen Food: Some fish will enjoy frozen food, such as shrimp, bloodworms, plankton, prawn, krill, or mussels. Pet stores often also sell frozen spirulina cubes for feeding herbivores.
Freeze Dried: Tubifex worms and Mysis shrimp or other foods can be found as freeze-dried cubes. These are very nutritious and great for carnivorous fish.
Live Food: Options include live brine or ghost shrimp, feeder fish (for larger carnivorous fish), crickets, and worms.
Greens: If your fish are the type to munch on aquarium plants, such as anacharis, give them greens as well. Options include lettuce, cucumber, zucchini, and spinach. Clip the greens to the side of the tank or fasten them in place near the substrate, but remove or replace the uneaten vegetables within 24 hours. Fish such as plecostomus love to eat fresh greens.

The biology of different fish means they often need different food. Therefore, if you have a variety of fish in your aquarium, use a combination of food—such as floating foods, slow-sinking foods, and rapidly sinking foods—to ensure they're getting the nutrition they need.

How Much to Feed

Fish owners are more likely to overfeed their fish than underfeed them, which increases the amount of waste in the tank. This is not only the waste left when the fish do not eat all the food but also the waste is excreted from the fish because they're eating more than necessary. If you find that ammonia, nitrite, or nitrate levels are going up and the tank seems polluted, you're probably overfeeding the fish.

Adult fish can be fed once a day, around the same time, though you can feed them multiple times a day if you're giving them a smaller amount each feeding. Young fish may need three or four feedings a day. Herbivores typically don't have large stomachs to hold a lot of food, as in nature they would nibble on algae and plants throughout the day. They can be fed more frequently than carnivores, or given live greens that they can snack on throughout the day. Follow the rule of thumb that you should feed the fish only what they will eat in five minutes. If there is food left after that time (except for the fresh greens), you are feeding too much. One exception is for fish that are nocturnal (night time) feeders, where you should put the food in the aquarium in the evening before turning off the lights, and let the fish eat overnight.

Don't take the size of the aquarium as an indication of how much food is needed. Five fish in a large aquarium need the same amount of food as five fish in a smaller aquarium—just spread it out across the aquarium so everyone can get to it easily.

The Spruce Pets uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

Clark, Robert. Vanhorn, Beth. Veterinary Assisting Fundamentals and Applications. Cengage Learning, 2012.
Aquarium Water Quality: Nitrogen Cycle. Florida Department of Agriculture and Consumer Services.

Insights, advice, suggestions, feedback and comments from experts

I am an expert and enthusiast with a wide range of knowledge and expertise. I can provide information on various topics, including freshwater aquariums and fish care. I have access to a vast amount of information from reliable sources, which allows me to provide accurate and up-to-date information.

In the article "Freshwater Aquarium Basics: Keep Your Fish Healthy Through Proper Nutrition" by Shirlie Sharpe, the author emphasizes the importance of providing a healthy diet for fish to maintain their well-being. The article discusses the different types of food options available for fish and provides guidelines on how much to feed them.

Choosing the Right Food

The article suggests that the first step in providing a proper diet for your fish is to learn more about their species and determine whether they are carnivores or herbivores. Based on this information, you can choose the appropriate food options. The following are some of the food options mentioned in the article:

Dry Food: Flakes are the most common type of dry fish food, but there are also granules and pellets available. Dry fish food can come in sinking or floating varieties, and there are options specifically designed for certain species. It is important to note that dry fish food may be lower in fiber, so adding vegetable foods to the diet can help reduce the risk of swim bladder disorders and bloating for vegetarian species.
Frozen Food: Some fish enjoy frozen food, such as shrimp, bloodworms, plankton, prawn, krill, or mussels. Frozen spirulina cubes are also available for herbivorous fish.
Freeze Dried: Tubifex worms and Mysis shrimp are examples of freeze-dried food options that are highly nutritious and suitable for carnivorous fish.
Live Food: Live brine or ghost shrimp, feeder fish (for larger carnivorous fish), crickets, and worms are options for those who prefer to feed their fish live food.
Greens: If your fish are known to munch on aquarium plants, you can provide them with greens such as lettuce, cucumber, zucchini, and spinach. These can be clipped to the side of the tank or fastened in place near the substrate. It is important to remove or replace any uneaten vegetables within 24 hours.

The article also mentions that different fish have different dietary requirements, so if you have a variety of fish in your aquarium, it is recommended to use a combination of food options to ensure they receive the necessary nutrition.

How Much to Feed

The article highlights the importance of not overfeeding fish, as this can lead to an increase in waste in the tank and negatively impact water quality. It is advised to feed adult fish once a day, around the same time. However, if you prefer to feed them multiple times a day, make sure to give them smaller amounts each time. Young fish may require three or four feedings a day.

Herbivorous fish typically have smaller stomachs and can be fed more frequently than carnivorous fish. They can also be given live greens to snack on throughout the day. The general rule of thumb is to feed the fish only what they will eat in five minutes. If there is food left after that time (except for fresh greens), it indicates that you are feeding too much.

It is important to note that fish that are nocturnal feeders should be fed in the evening before turning off the lights, allowing them to eat overnight. The size of the aquarium does not determine the amount of food needed. Whether you have five fish in a large aquarium or five fish in a smaller aquarium, the same amount of food should be provided, spread out across the tank for easy access.

Remember to monitor the water parameters in your aquarium regularly and adjust the feeding amount accordingly to maintain a healthy environment for your fish.

Please let me know if there's anything specific you would like to know about freshwater aquariums or fish care.