The term for swimming up and down the tank is ‘glass surfing.’ The most likely cause behind this eccentric behavior is an unsuitable environment. It could be a cramped tank, toxic water parameters, or an entirely new environment. However, other times, the reason could be something as simple as boredom and chasing own reflection! 

The main differentiating factor is the black botch that’s located right beneath the dorsal fins. In males, this spot has a stark black color. In females, it has hints of iridescent blue here and there.

Yes, oscar fish sleep. They retire to their favorite corners at the bottom of the fish tank and call it a night. Like us, they have sleep cycles. And their body also produces hormones that regulate their sleeping pattern and calibrate their internal clocks. 

When freshly laid, oscar fish eggs are white in color. They are slightly bigger than a salt flake – about a millimeter in diameter. But the following day or so, they start to look like a mini chocolate ball. Since the matriarch lays hundreds of eggs, it looks like someone just scattered some salt on the rock. 

No, you cannot keep oscars with African cichlids. For starters, they come from two different corners of the world and need entirely different water parameters. Second, both oscars and African cichlids are aggressive fish. At least one party will be relentlessly bullied, which can lead to grave injuries and even death. 

No, you cannot keep oscars with goldfish. I could bombard you with all the reasons they shouldn’t be housed together. But for starters, oscars will eat your goldfish 9 out of 10 times. 

Yes, oscars have teeth. In fact, they have 2 sets of teeth – one in their jaws and another in their throat. The teeth in the jaws are small and used primarily for grasping. Whereas the pharyngeal teeth in the throat are used to manipulate and process the prey.