What Does a Rainbow Shark Eat: Your Ultimate Guide for Your Pet Fish’s Diet

Rainbow sharks mostly eat small fish, crustaceans, and live foods, such as insect larvae and tubifex worms. As with any fish, the diet of a rainbow shark in an aquarium should be tailored to its individual needs. However, a good diet for this species in an aquarium may include sardines, anchovies, shrimps, crabs, insects, worms, and some fresh vegetables.

Ideal Diet of Rainbow Shark in Aquariums

So, as with all aquarium fish, it is essential to research the specific dietary needs of your rainbow shark before setting out to purchase food. In addition, it is also a good idea to change the diet regularly and to supplement it with fresh food if necessary.


A few types of vegetables can be offered as a portion of supplementary food to rainbow sharks in captivity. Some examples include sliced cucumbers, cherry tomatoes, peas, green beans, and carrots. Please ensure the vegetables are cut into small pieces, so they do not overwhelm the shark’s stomach and cause uncomfortable bloating or gas accumulation.

If you choose to give your rainbow shark a vegetable supplement, make sure it is high in fiber and low in salt. Additionally, choose only fresh, never processed vegetables.

Frozen Food 

Some people choose to feed their rainbow sharks a diet made up of frozen food. While this may work for some sharks, it is not necessarily suitable for all types of fish. In addition, depending on the brand and type of frozen food chosen, feeding your rainbow shark this type of diet can be high in salt and sugar.

However, just like with any fish, ensure that the food you provide your rainbow shark is of the highest quality and appropriately sized for their size.

In addition, if you choose to feed your rainbow shark frozen food, ensure it is stored in an airtight container and consumed within a short period.

Flake Fish Food

Another option for providing supplementary food to rainbow sharks is flake fish food. While this diet can also be high in salt and sugar, it does not contain meat or bones, which can be problematic for some shark species. Flake fish foods are also relatively easy to administer and provide a good source of vitamins, minerals, and other essential nutrients.

Additionally, all types of flaked fish food can be frozen and fed as a solid diet, making it an ideal choice for those who do not have access to live prey.

Living Food

If you provide your rainbow shark with live prey, select a species compatible with their tank size and appetite. Some of the best options include stingrays, small catfish, or goldfish.

While all types of live food can be dangerous if ingested in large amounts, smaller portions should not pose a problem for most sharks. In addition, make sure the food is fresh and cleaned adequately before feeding it to your rainbow shark.


Algae is another option for rainbow shark food and can be a good choice if you are looking for a high-quality, low-calorie supplemental diet. Algae contain nutrients such as zinc, selenium, and copper, which can support the growth of your shark tank.

Additionally, algae is an excellent source of protein and can be fed to rainbow sharks in small doses as part of their regular diet.

While algae may not provide all the essential nutrients that other types of fish food do, it is affordable to supplement your rainbow shark’s diet without spending much money.

Brine Shrimp

Brine shrimp are another excellent option for supplemental food for rainbow sharks. Like algae, brine shrimp contain various essential nutrients that can support the growth and health of your shark tank. In addition to supporting the health of your rainbow shark, brine shrimp also provide plenty of protein, making them an ideal choice as a primary food source.

While brine shrimp may be more expensive than some other fish food, they are well worth it if you want to provide your shark with high-quality nutrition.

Rainbow Shark Feeding Schedule

Feeding rainbow sharks is essential to their overall care and should be done regularly. Feeding your shark food twice to thrice daily will give them the essential nutrients to stay healthy and active.

In addition, feeding rainbow sharks food regularly will discourage them from eating items that may be harmful to their health, such as plastic or other debris in the tank.

Ways of Feeding Rainbow Sharks Safely

There are a few different ways you can feed rainbow sharks. For example, you can put food directly into the tank or feed them via a feeding tube.

  • To feed rainbow sharks directly, place small amounts of food into a bowl and then pour the food into the tank. Keep an eye on your rainbow shark, so they don’t overeat and get overweight.
  • If your rainbow shark is eating well with direct feeding, you may consider purchasing an automatic fish Feeder that will dispense food automatically at precise intervals. This way, you won’t have to worry about feeding your shark food regularly.
  • Feeding rainbow sharks via a feeding tube is another option you may want to consider. Feeding tubes come in different sizes and can be attached to the side of the tank or directly into the water column.
  • Place food down the feeding tube and watch as your shark grabs it with their teeth and eats it right from under the water surface. 

How Long Can Rainbow Shark Survive Without Food?

Most rainbow sharks can survive for three days to a week without food. If a shark does not eat for a prolonged period, its body will start cannibalizing other fish in the tank.

Additionally, if your fish is not eating, look at their water quality and make sure it is clean and healthy. It’s essential to provide them with a regular diet of live aquatic insects and earthworms to restore their health as quickly as possible. So, monitor your fish’s health and feeding habits closely.