Oscar fish bite their tankmates under stressful conditions. They bite due to unfavorable water parameters, food scarcity, mating competition, poor tank conditions, stress, or to defend their territory. Oscars also bite humans if they aren’t used to seeing their hands in the tank water.
Let’s now understand the various factors that trigger oscars to bite.
Why Do Oscar Fish Bite?
Oscars can become territorial and resort to biting due to various factors. The most prominent reasons are listed below.
Oscars are hardy fish, but they also get stressed easily. When stressed, oscars can get irritated and start biting.
Stress can get triggered by numerous factors such as food scarcity, space constraints, mating competition, poor water conditions, constant bullying, and territorial dispute.
Stress also negatively impacts oscars’ health by weakening their immune system and making them more prone to various diseases.
Oscars are territorial fish. They vehemently defend their territory against intruders. This is their natural behavior, even in the wild.
The size of the territory varies according to the aggressiveness, size, and surroundings.
Once the territory is established, oscars vigorously defend it by chasing away other fish.
If the other fish don’t move away and continue to invade their space, the oscars become aggressive and bite the other fish to defend their territory.
Territorial disputes among oscars can occur when there is inadequate space in the aquarium.
3. Food Scarcity
Food scarcity is one of the significant reasons for oscar fish to bite.
If the food is scarce, oscars will fight among themselves for the limited food resource.
They can even bite other fish to drive them away from the meal.
So it’s crucial to provide adequate food and spread it out evenly throughout the tank.
This will ensure that all the fish are well-fed and happy.
4. Mating Competition
The most common cause of biting among oscars is mating competition.
Oscars have a strong urge to mate in the breeding season. So male oscars are constantly on the lookout for females to mate with.
If there are too many male oscars and fewer females in the tank, it leads to fighting.
Male oscars will fiercely compete with each other to get access to the females.
Male oscars can even become restless and harass the females.
They will aggressively chase the females and attempt to force them into spawning.
This can result in fighting and eventually end up in biting.
So it’s vital to maintain a male-to-female ratio of 1:3.
This ratio will ensure that the tank has enough females to breed, and there will be no fighting over females.
5. Poor Water Conditions
Poor water conditions can also cause oscars to bite. Oscars need clean water to thrive.
If the water is contaminated, they can get stressed due to unhealthy living conditions.
The water can get polluted due to the increase in the tank’s ammonia, nitrates, and nitrite levels.
Oscars can then become aggressive and start attacking other fish.
Even a clogged filter accumulates waste, leading to a higher concentration of ammonia and nitrites in the tank water.
An increase in these levels can cause stress to oscars leading to aggressive behavior such as biting.
So it’s essential to keep the water quality optimum.
Overcrowding is another primary reason for oscars to bite. Oscars are big fish that grow over 12 inches long in captivity.
They grow very fast at a rate of 1 inch per month in the first year. So oscars need a larger tank with ample space.
They can get restless in an overcrowded tank, resulting in biting.
The more the number of fish in the tank, the more they will compete for food resources, space, and mates.
This can result in stress, leading to aggressive behavior.
7. Unfavorable Water Parameters
Ideal water parameters are critical for oscars to live a healthy life.
If the water parameters aren’t suitable, it can stress the oscars and negatively impact their health.
Oscars can also become aggressive under stressful conditions and display erratic behavior such as biting.
Factors such as water temperature, pH level, water hardness, etc., should be in the desired range for oscars to thrive.
Given below are the ideal water parameters for oscars.
Water Temperature 74°F to 81°F (23.3°C to 27.2°C)
pH Level 6 to 8
Water Hardness 5 to 20 dH
Alright! Now that you’re aware of the factors that trigger oscars’ aggressiveness, you must be wondering whether their bite will hurt?
So let’s understand this.
Do Oscars’ Bite Hurt?
An oscar’s bite doesn’t hurt because it’s a suction feeder.
Suction feeder fish have small teeth in their mouth to grip the food.
They tear, bite, chew, and spit out the food to break it down for ingestion.
Similarly, oscars have minuscule teeth for gulping small prey such as bugs and other tiny crustaceans.
So even if they bite human skin, the bite isn’t likely to cause any fatal damage. At the most, it may cause minor abrasion to the skin.
However, an oscar’s bite can be detrimental to smaller fish. It can lead to lifetime impairment or, in worst cases, can even be fatal.
Do Oscar Fish Bite Their Tankmates?
Yes, oscars can bite their tankmates. Oscars belong to the cichlid family.
So they exhibit typical aggressive characteristics of cichlids. They’re also highly territorial similar to cichlids.
That’s why oscars can get aggressive and bite their tankmates if they intrude in their territory.
Oscars can nip the fins or tails of their tankmates and cause abrasion.
Given below are some of the reasons that can make oscars bite:
- The tank is overcrowded.
- There’s food scarcity.
- New fish are introduced into the tank. Oscars can bite the new fish to exert dominance.
- Water quality is poor.
- Water parameters are unfavorable.
It’s crucial to keep a close eye when oscars get aggressive and start biting their tankmates.
Don’t let these fights carry on for a longer period as they can lead to severe injuries.
Can You Train Oscar Fish Not To Bite?
Yes, you can train oscar fish not to bite when they’re young. Hand-feeding is a great way to teach them not to bite aggressively.
This technique works best with baby oscars rather than fully-grown adult oscars.
Adult oscars may attempt to bite your fingers if you hand feed them as they’re not used to seeing a human hand.
Moreover, a young oscar’s teeth are softer and more adaptable in a new habitat.
So it’s worth taking the risk of training your oscar fish when they’re young.
You can start with a finger or rubber gloves on your thumb and index finger. Training them takes time, so patience is the key.
Do oscar fish bite humans?
Oscar fish can bite humans when frightened. So you need to be careful while cleaning the tank or performing water changes.
Biting also depends on the individual fish and its temperament.
If oscars have not seen human hands before, they may feel threatened and bite in defense.
Do oscar fish have teeth?
Oscar fish have two sets of teeth – one in their jaws and the other one in their throat.
The teeth in their jaws are usually small and primarily meant to grip or grasp the food.
In contrast, the pharyngeal teeth in the throat help them break down and process larger bits of food and prey.