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Why Oscar Fish Not Eating? 5 Things to Consider

Although Oscars are not known to be particularly picky, they can suddenly become so if there is an underlying problem. If you notice that your Oscar doesn’t want to consume any food, then you need to keep a close eye on him.

The Oscar fish is an omnivorous species of fish and there are many foods that this little guy can eat. A big part of its diet should consist of meat-based foods. Insect larvae, chicken meat, beef heart, carnivore pellets are all good for them.

Small amounts of vegetables and fruits should complement their diet 3-4 times per week. It’s as simple as that but this can quickly become problematic. The problem usually arises when fish keepers provide low-quality foods, overfeed their pet or don’t prepare the food properly.

But your Oscar can also refuse to eat because of a disease or stress-related issues. In this article, we are going to talk about these problems and explain what you can do about them.

Reasons Oscar Fish Refuse to Eat

Keeping an Oscar fish at home can be simple for someone who has a lot of experience. There are some things that are straightforward for them that are not so clear for the beginner. However, sometimes even the more experienced fish keepers fall into one or more of the mistakes we are going to talk about below.

The important thing to understand that providing your fish with a well-balanced diet is sometimes not enough. There are also environmental factors that can affect their health. If they are under a lot of stress, they are going to refuse to eat.

The same can be caused by other types of unease such as diseases or parasites. Now let’s see what are the main factors that can affect the diet of your Oscar.

New Environment

Unfortunately, your fish is not going to feel at home right after you bring him home from the pet store. He needs time to adapt to the new environment. Even if you did your best to set up the perfect tank for your Oscar, it is going to be a stressful experience for him in the first few days.

It is completely normal if your fish doesn’t want to eat until he gets accustomed to the aquarium. Out in the wild, wandering to unexplored underwater areas means that there can be various threats. There can be predators lurking, looking to catch those fish off-guard.

Over time, your Oscar will realize that there is nothing to be afraid of and that it’s his own safe territory. Meanwhile, you can try to feed him and collect the leftover foods afterward if he still refuses to eat.

Don’t like the Food

We can’t stress enough how important it is to feed your Oscar with high-quality foods. If even your pet knows that it’s bad, then you can only imagine how bad that food actually is. There are plenty of cheap commercially made foods that we would not recommend feeding to an Oscar.

He might eat it but it is certainly not good for his health on the long term. Your fish not eating the food can also mean that it’s expired. Besides checking the nutritional value on the package, you also need to keep track on the expiration date.

Vegetables, fruits and meat-based foods all have to be clean. You need to prepare them by removing the peel, washing them or blanching them before feeding. By doing so, you remove all the harmful pesticides, bacteria or parts that are not even edible.

Water Parameters

When the water parameters are not on-point, it can cause a lot of stress to your Oscar. You need to change the water by removing some and pouring in some clean water every week. Oscars prefer the water temperature to be 74 to 81 degrees Fahrenheit.

Keeping the acidity between 6-8 pH and the water hardness between 5-20 KH is also important. Large deviations can cause your Oscar to become stressed and lose appetite.

Stress due to Aggressive Mates

This is a big one because aggressive mates that are constantly threatening your Oscar can cause a lot of stress. If you keep him together with bigger tank mates that are also aggressive and territorial, then your Oscar is going to suffer from a lot of stress.

It is not rare for these types of tank mates to attack and hurt or even kill your fish. Constantly being afraid significantly lowers their appetite because they are constantly on the lookout for threats. In a home aquarium, your pet needs to feel safe.

This is why it is so important to choose tank mates that are compatible with your Oscar. If those tank mates are too small and passive, then your Oscar might be the one to bully them, which is not good either.

Disease or Parasite

Oscars absolutely love to eat smaller fish. Besides the other carnivore foods, it is important to feed them feeder fish occasionally. Now the problem with feeder fish is that you can fall into the mistake of not getting it from a reputable source.

For example, the way many pet stores breed Guppies and Goldfish is they do it in large amounts. They keep all those fish together and they can get various parasites and diseases. By buying them and feeding them to your Oscar, he can get infected by those.

When it comes to feeder fish, your best alternative is to breed them at home. Besides that, your fish not eating can be also a sign that he is sick.

Wrapping Up

We can conclude that there can be many problems behind your Oscar refusing to eat. In general, Oscars don’t have a problem with their appetite if their owner takes proper care of them. Keeping the water clean, the diet healthy and the water parameters on-point also prevents diseases.

So, if your Oscar does not want to eat, there is probably something missing. Make sure to go through each of the points we talked about above and you are going to figure out what is the problem.

avatar I’m Julia, and I used to work in a fish store for over 5 years. On this blog I help beginners care for their cichlids and share my experience and research on various fishkeeping related topics.

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