What to do if You Run Out of Fish Food? – Fish Food Alternatives

There are various fish food options available out there, but sometimes it gets really boring for our little pets. One has to wonder, what other options are there besides fish food?

You also need to know about these options to have a backup, in case you run out of fish food some day. 

So, what can fish eat besides fish food?

Fish can eat boiled vegetables like cucumber, leafy greens, shelled peas, fruits, and cooked seafood. Finely chopped or sliced frozen food, especially fish filets, can also be fed when you run out of fish food.

In this blog, we’ll read in detail about what to do and what not to do if you run out of store-bought fish food. 

Fish Food Alternatives for Different Types of Fish

Marine fish have a varied diet in the wild. Your aquarium fish may actually enjoy eating when you feed them something other than fish flakes. However, the food items you choose should be suitable for the fish’s digestive system and dietary requirements. 

Whether you are looking for fish food alternatives to supplement your pet’s diet, or to replace commercial fish food, you should always consider your fish’s digestive system and specific requirements first.

Here are some alternatives to fish food that different types of fish can eat:

For Carnivores

Carnivorous fish have large stomachs and short intestinal tracts. Though some carnivores like betta fish can eat algae and plant-based foods, most of them cannot extract nutrients from plant food and need a meat-based diet to stay healthy. 

Large carnivorous fish can consume an entire small fish. 

Carnivorous fish can eat the following live and frozen foods besides the fish food: 

  • Brine shrimp 
  • Bloodworms
  • Mealworms
  • Snails 
  • White fish 
  • Beef heart
  • Frozen fish filets, etc. 
  • Daphnia
  • Earthworms
  • Crickets, etc. 

However, carnivore fish shouldn’t have fatty or oily foods with more than 6% fat. Some of them are picky eaters, so it may take a while for your carnivore to enjoy the bits of meat you dropped into the fish tank. 

For Herbivores

Unlike carnivorous fish, herbivorous fish live on plant-based nutrients and enjoy eating live aquatic plants. 

Herbivorous fish have smaller stomachs and need frequent feedings. However, you should be careful not to overfeed them as it leads to digestive issues like constipation. You can feed herbivorous fish a variety of vegetables, greens, and fruits, such as

  • Cucumbers
  • Softened peas
  • Boiled veggies (cauliflower, carrots, sweet potato, broccoli) 
  • Apples
  • Strawberries
  • Bananas
  • Duckweed
  • Brazilian waterweed, etc., 
  • Leafy greens (spinach, lettuce, kale)
  • Spirulina, etc. 

Most plant-eating fish are inquisitive and like to try new foods. You’ll find it easy to feed them something other than commercial fish flakes or pellets. 

For Omnivores

Omnivorous fish eat plant and animal-based foods. Their digestive systems can process both kinds of food and provide the necessary nutrients to their bodies. Most fish come under this category, making it easy to find fish food alternatives without stressing out too much. 

However, you may notice that some omnivore fish have a preference for meat, while some are not picky. Observe what your aquarium fish enjoy the most by trying different options like 

  • Snails
  • Hard-boiled egg yolk
  • Snails
  • Shrimp
  • Lettuce
  • Spinach
  • Boiled cauliflower
  • Duckweed
  • Insect larvae
  • Cucumber
  • Zucchini, etc. 

Most omnivorous fish may need to fast for two to three days before they can eat other types of food. This is normal and nothing to worry about as long as they start eating soon. 

Fish/ FoodCarnivorous FishHerbivorous FishOmnivorous Fish
Plant-Based FoodNot recommendedBoiled/ steamed cucumber, spinach, lettuce, sweet potato, apples, raspberries, melon, peas, etc.Boiled/ steamed zucchini, kale, peas, lettuce, sweet potato, apples, banana, melon, etc.
Animal-Based FoodCod, white fish, beef heart, etc. Not recommendedWhite fish, salmon, cod, hard boiled egg yolks, etc. 
Live/ Freeze Dried FoodBlood worms, shrimp, daphnia, etc. Not recommended unless it is frozen vegetable pureeBlood worms, shrimp, daphnia, etc.

What Types of Human Food Can Fish Eat?

Fish can eat almost every human food that you feed them, but not everything will be healthy and appropriate for every fish species. For example, canned food is never recommended as it has additives and preservatives that can harm your fish. 

Cooked human food with seasoning and flavors should not be fed as it contains additional ingredients like salt, sugar, and spices, which are not suitable for the fish’s digestive system. Pickled or wilted vegetables should also be avoided.

Let’s have a look at several classes of human food, and how well they suit various fish species:



Plant-eating fish and omnivorous fish enjoy human foods like green vegetables and boiled roots available in your kitchen. Vegetables (without too much water or oil content) are a great source of nutrients as well, such as the blanched and shelled peas, which are perfect natural laxatives for fish. 

Some vegetables, such as cauliflower, and roots like carrots, sweet potatoes, etc., have to be boiled or steamed before feeding your fish. Raw root vegetables are not a safe choice. However, don’t sauté them with butter or spices. Wash the vegetables and leafy greens thoroughly to get rid of pesticides. 

  • Avoid using acidic and strong flavored vegetables. 
  • Lettuce, spinach, kale, and other greens should also be blanched and chopped into small pieces. 
  • Frozen peas should be thawed, cooked, and shelled.
  • For cucumber and zucchini, remove the soft insides and seeds.
  • Vegetables decompose fast and can rot in the aquarium, causing ammonia spike and turning the water toxic. To deal with that, make sure you remove the leftover food from the fish tank when you are feeding green vegetables to your fish. 


Small quantities of healthy fruit provide the necessary vitamins and minerals to your fish. Fruits are great as fresh food and an occasional treat to pamper your pet fish. 

Herbivorous and omnivorous fish enjoy eating fruits once in a while. However, fruits are not recommended for meat-eating fish, even if betta fish may consume fruits like apples. 

When you are feeding fruit as fish food alternatives, make sure that you wash it thoroughly and chop it into tiny bits. Remember that larger fruit pieces can harm small fish (like goldfish) and cause them to choke on their food. 

Fruits don’t have to be cooked or steamed and are enjoyed even by water snails. 

However, fruits should not be a staple diet of fish. Peel the skin to remove pesticides and wax on apples and pears. Avocado is poisonous to fish and many house pets as it contains persin. 

Here are the most popular fruits with the fish species they suit the most:

Apple Goldfish, Betta fish, Cichlids, Snails 
BananaBetta fish, Molly fish, Goldfish 
Grape Goldfish, Molly, Cichlids
StrawberryGoldfish, Cichlids, Barbs, Gourami, Tetra fish
Mango Goldfish, Bettas, Cichlids, Guppies
WatermelonGoldfish, Koi, African Cichlids

Hard Boiled Egg Yolks

Hard-boiled egg yolk is a popular human food for fish fry and newborns of livebearers. Cherry shrimp also enjoy eating little chunks of hard-boiled egg yolk. You can feed egg yolk as an occasional food to omnivorous fish when fish food is not available, or when you need a change.

Make sure not to feed raw or undercooked egg yolks. It makes the fish tank messy and changes the chemical composition of the water. The fish tank will look hazy and muddy when the leftover egg yolk mixes with the water and begins to decompose. 


Carnivore fish enjoy white fish filets, frozen fish filets of cod, tilapia, salmon, etc. However, fish don’t eat seafood the way we do. You shouldn’t saute the fish filets in butter or add a dash of lemon juice when you are feeding them to your fish. 

Large carnivorous fish eat smaller fish in the wild and can do the same in the fish tank. Thaw frozen seafood, chop it into small bits and add to the fish tank. 

Animal Organs  

Beef heart and chicken liver are low-fat foods suitable for meat-eating fish.  Similar to seafood, the organ meat of farm animals should not be seasoned. Note that occasionally feeding organ meat to fish is fine but the meat from flesh is not recommended.

Some fish keepers still experiment and even feed scraps of chicken to their pet fish. However, excess fat in meat can damage the reproductive system, liver, and heart of your fish and lead to premature death. 

Rice and Pasta

Fish actually like eating rice and pasta. Fish eat rice, but only boiled rice or pasta (broken into smaller pieces) is safe for them. When you are feeding rice and pasta to your fish, make sure they do not contain salt or spices. 

Also, avoid using uncooked grains, as grains are hard and some fish will swallow them or choke on them. Furthermore, uncooked rice will expand inside the fish’s belly and lead to serious digestive issues like bloating. 

However, try to limit feeding rice and pasta as they are not the primary foods for fish and cannot be found in the wild.

Can Fish Eat Homemade Food?

Fish can definitely eat homemade fish food as long as it caters the specific needs of a fish species.

Since many fish species (omnivores and herbivores) eat vegetables, you can prepare larger batches of homemade food and store them in the freezer. 

All you have to do is bring together all the favorite vegetables and fruits, cook or boil until tender, and make a puree. Create gelatin or agar solution (binding agents) on the side and mix it with the puree. You can safely freeze this puree into ice cubes as well!

You can follow a similar process to feed homemade fish food to your carnivorous fish. White fish, salmon, cod, and shrimp are the most commonly used ingredients to feed carnivorous fish. The ingredients can be cooked or uncooked. 

For vegetables like cucumber, you can cut it in half and scoop the soft white inside and seeds. Then lower the remaining cucumber flesh into the fish tank. Bottom feeders will enjoy nibbling at the cucumber over the next few days. 

Homemade fish food is quick and simple, when it comes to alternatives to fish food. It is safe for most fish types. However, tiny fish like Nano fish may end up overeating homemade fish food due to their tiny size. 

Factors to Keep in Mind When Feeding Fish Food Alternatives 

Fish can eat a lot of things besides fish food, which looks quite attractive, as it makes fish parents’ lives super easy. But there are a lot of factors to keep in mind when you are considering fish food alternatives.

  • Type of Fish

When you are feeding your fish anything other than the fish food, the type of fish is the most important factor. Carnivores cannot digest plant-based foods, and the herbivores cannot thrive on animal-based foods. 

  • Quality of Ingredients

Buy premium quality raw ingredients with additional flavors or seasonings. Opt for organic vegetables and fruits to reduce the risk of pesticides. Thoroughly wash and peel the vegetables and fruits to get rid of chemicals and wax coatings on them. 

Avoid using overcooked or undercooked food for your fish.

  • Freezing and Storage 

Homemade fish food has to be frozen properly in airtight containers and kept in hygienic conditions. Remove the required quantity and put the rest back in the freezer. Thaw the day’s portion before feeding your fish. 

  • Feeding Your Fish  

Fish foods come with serving portions. But when we are using fish food alternatives, it is easy to overfeed them, which can be disastrous for fish’s health. 

Never feed the pet fish from your plate. While it may not harm your dogs and cats, the seasonings will affect your fish’s health. The oil or butter from food can add a film to the aquarium water’s surface and lead to breathing difficulties in the fish.

What to Never Feed Your Pet Fish

The fish in your aquarium may eat whatever you give them, even if the foods are not good for their health. But there still are some food options that should never be made available to your aquarium fish. 

Dog Food

A few fish breeders have trained their fish to eat dog food to help the fish grow bigger. However, it is not recommended as dog food causes belly fat and obesity issues in the aquarium fish. 

Cat Food

Cat food can be considered similar to fish food as both tend to be seafood-based. However, cat food has high protein content, which is not suitable for all types of fish. It may lead to protein film and an oily layer on the water. 

Animal Meats

Fish are aquatic animals and survive on seafood in the wild. Carnivores may occasionally eat other live food, but not regularly. Meat from farmed animals cannot be properly digested by fish. You should not feed fish cooked or raw meats like chicken, beef, pork, sheep, rabbits, etc. 


When fish eat bread, they end up falling sick. Bread is made using wheat flour and yeast, sugar, salt, and preservatives, which cause bloating, constipation, and digestive issues in fish


While cooked corn meal can be fed to fish, raw corn kernels and popcorn are a risky choice. Small fish that gobble up food will choke on the corn kernels. Popcorn leftovers can make the fish tank messy. 

Biscuits and Cookies

Biscuits and cookies have high sugar content and are made of wheat flour. Wheat is a filler ingredient that doesn’t provide any nutritional value to fish. Other ingredients like corn starch, essence, food colors, etc., are also harmful for the aquarium fish.

canned food


You can provide your pet fish an array of other items if you run out of fish food. While some fish immediately take to new foods, a few others may be picky and wait a day or two before trying something different. 

Make it a point to scoop out leftover foods from the fish tank to prevent water contamination. Also, remember that processed fish food flakes, pellets, etc., should continue to be a part of your fish’s diet. Stock up on commercial fish food when you can and go for alternatives once or twice a week. 


What can I feed my tropical fish if I don’t have fish food?

Tropical fish species prefer soft vegetables like cooked peas, cucumbers, spinach, lettuce, parsley, etc. Large tropical fish can eat slightly better chunks of cooked carrots, broccoli, and zucchini.

What real food can betta fish eat?

Insect larvae and aquatic flies are a better choice of feed for betta fish. They also eat shrimp, smaller fish, and worms. Boiled and shelled peas have to be chopped into smaller pieces when feeding betta fish. 

What homemade food can you give goldfish to eat?

Small pieces of shrimp, cooked vegetables, chopped leafy vegetables, and shelled peas are some homemade food items to feed your goldfish. They also enjoy fruits like strawberries and mangoes. 

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