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Why Is My Oscar Fish Not Eating? (5 Causes to Consider)

Why Is My Oscar Fish Not Eating? (5 Causes to Consider)

This post is written to the author's best knowledge and is not intended to be used in place of veterinary advice. In addtion, this post may contain affiliate links. As an Amazon Associate I earn from qualifying purchases.

Taking care of Oscar fish is generally simple. These are hardy types of cichlids that are pretty good for beginners.

If you have room for a big fish tank, taking care of Oscars won’t be that hard. Of course, things can still go wrong sometimes.

Have you had a tough time getting your Oscar fish to eat as of late? Under normal circumstances, Oscars are voracious eaters.

When Oscars stop eating, it’s generally a sign that something is amiss. There is likely some issue that you need to get to the bottom of.

Below, you’ll learn about the reasons why Oscars will stop eating. This should help you to determine how to move forward by allowing you to troubleshoot your situation.

My New Oscar Fish Is Not Eating

Sometimes new Oscars might not eat right away. It’s normal for fish to be shy when they are first introduced to a tank.

Are you noticing that the new Oscar fish seems a bit skittish? Perhaps it’s hiding more than usual and it isn’t roaming the tank too much.

This might simply mean that the fish needs a bit of time to acclimate to its new environment. If this is the case, it’ll probably be fine if you give the fish several days or even a week to get used to things.

Being transported to a new aquarium is a stressful process for a fish. The conditions in the pet store tank were likely much different than the tank that you put the Oscar fish into as well.

Your tank is likely much closer to ideal for the Oscar fish, but it’ll still need time to adjust. Give it a bit of time and do your best to meet its basic care needs.

Everything will likely be okay. If the fish still doesn’t eat normally after a good bit of time has passed, you might need to look into other things that might be wrong.

Oscar Fish Not Eating Pellets

What does it mean when Oscars won’t eat fish pellets? Normally, Oscars will happily eat fish pellets.

It’s common to feed Oscars nutritional pellets that are formulated for large cichlids. If they’re not eating what you’re giving to them, it’s likely that something is wrong.

The first thing to consider is whether the nutritional pellets are appropriate for Oscars. Are you feeding them nutritional pellets that are meant for Oscar fish?

Perhaps you’re giving them pellets that are meant for other types of fish. If you’re using recommended pellets, it seems unusual for Oscars to not eat them.

It could be that the Oscar fish is bored of what you’re feeding it, too. Sometimes the Oscar fish might stop eating in an attempt to hold out for something better.

1 – Your Oscar Might Want Live Food

If you only feed the Oscars flakes and pellets, it’ll get bored of what you’re giving it. You might simply need to feed the fish more enticing foods to get it to eat again.

Oscar fish love to be fed meaty treats. You should be supplementing the diet of the Oscars with meat-based foods.

There are many different options that you can consider, but many enthusiasts go with live food. You can feed Oscars live shrimp, worms, and other types of live food.

Try buying different types of live food from the pet store to give to your Oscars. The fish will truly appreciate such feasts.

If you don’t like giving fish live food, it’s fine to go with other options. For instance, you could purchase freeze-dried foods to give to the Oscars. It’s easy enough to get different types of freeze-dried worms and shrimp to give to Oscars.

Frozen shrimp are also an option. You simply need to thaw the food out before you give it to the fish.

Do your best to vary your Oscar fish’s diet from now on. It should lead to much better results.

2 – Giving the Fish Bad Food

Giving the fish bad food might make it turn away. Your fish might choose to avoid eating certain types of food.

Also, Oscars might not eat food that isn’t cleaned properly. People often feed Oscars veggies and meat-based foods.

These foods are supposed to be clean and cut up into proper chunks. When trying to feed Oscars veggies or fruits, you need to make sure that they don’t have any seeds, peels, or pits.

Remember that washing is an important part of the process. It removes pesticides, bacteria, and other potentially harmful elements.

3 – General Stress

General stress will sometimes keep Oscars from eating normally. When fish become stressed, they won’t act the same as they usually do.

An Oscar fish can become stressed for many different reasons. It could have to do with being forced to live in a cramped environment.

Since Oscars are large fish, it makes sense that they would need large tanks. You could have the Oscar living in a tank that’s a bit too small.

It’s also possible that the Oscar fish could be in an overcrowded tank. When Oscars are in community tanks, they might even get bullied by other fish if you don’t pick out compatible tank mates.

Any of these things could cause an Oscar fish to stop eating. If the fish is hiding and doesn’t come out when it’s time to eat, it’s a sign of severe stress.

You need to determine what is wrong in the tank and change things. If you don’t take action, the fish could eventually die due to sickness and lack of nutrition.

4 – Problems with Water Parameters

Problems with water parameters are also known to make Oscars stop eating. Sometimes these fish won’t eat when the water gets very dirty or out of control.

Oscars don’t like it when the water gets too cold. Generally, it’s best to keep the temperature between 75 degrees Fahrenheit and 80 degrees Fahrenheit, but some say 74 degrees Fahrenheit and 81 degrees Fahrenheit is the right range.

Either way, you don’t want the temperatures to be far outside of this range. The fish won’t do well if the water gets way too hot or too cold.

The pH balance of the water matters as well. It needs to stay between 6.0 and 8.0 with the ideal pH balance being 7.2.

Test the conditions of the tank regularly and do tank maintenance such as cleaning the tank and changing the water each week. This will keep your fish in good condition.

5 – Diseases, Infections, and Parasites

Another thing that can cause Oscar fish to stop eating is a disease. Oscar fish are susceptible to different types of diseases, infections, and parasites.

Sometimes certain types of illnesses will cause the fish to lose their appetites. This is a common symptom, and that makes it hard to determine exactly what sickness your fish has.

You’ll have to pay attention to other symptoms and what’s going on in the tank. This will give you the best chance of diagnosing the fish.

Many things could be happening. Your fish could be dealing with parasites, bacterial infections, or a standard type of sickness.

If you need help, you can contact an exotic veterinarian. This will allow you to get the fish diagnosed fast so you can work on finding the right treatment plan.

How Long Can an Oscar Go Without Eating?

You might be wondering how long an Oscar fish can go without eating. This depends on various factors such as age and size.

Generally, a juvenile Oscar fish is only going to be able to go for as long as two weeks without food. It might not be able to go this long depending on the situation, though.

A healthy adult Oscar fish is said to be able to go up to four weeks without eating. However, you should be feeding your fish daily to keep them in good health.

You don’t want to go too long without feeding your fish since it can lead to stress. Stress makes it more likely that your fish will get sick.

If you miss a few days because you weren’t home, it’s likely going to be okay. Even so, it’s best to stick to a normal feeding schedule to get the best results when caring for Oscars.

Final Thoughts

You should have a much better idea of what causes Oscars to stop eating now. If your Oscar fish isn’t eating, there are many things to consider.

It’s possible that your Oscar is simply bored of the food that you’re giving to it. You might need to do a better job of varying the food that you give to the fish by mixing in meaty treats.

The fish could be stressed due to problems in the tank. This can happen for many reasons such as water parameter issues, overcrowded fish tanks, and bullying.

You want to solve problems with stress as soon as you can. Fish can easily get sick when they become stressed.

Problems with food quality should be examined as well. Make sure that you buy high-quality food and do your best to clean food items such as fruits, veggies, and meat-based treats before giving them to your fish.

If you’re doing your best, it should be possible to turn things around. Even if the fish is sick, finding the right treatment plan should get it better and it’ll start to eat normally again.