Can you keep Oscars and green terrors together? If so, how many can I keep in my aquarium?

[CeruleanRosee]

I have a 42×12×18 aquarium (length, breadth, height). This is my first time getting a tank of this size and I was thinking of keeping a few monster fish in it.

I really like Oscars and my friend suggested that I could keep gts with them. I wanted to cross check whether that is true. Please help.

 

[robert_gorajski]

Hi,

I hope you don't take my comments as criticism, but I'd like to share my experience. Unfortunately, a 55-gallon tank (around 208 liters) is definitely too little space even for a single adult Oscar. These beautiful fish grow to really considerable sizes, often exceeding 30 cm (around 12 inches), and they need a lot of swimming space and produce a significant amount of waste. In such a small tank, an adult Oscar will struggle, which can lead to health problems, deformities, and a shortened lifespan.

When it comes to pairing it with a Green Terror, which is also a large and territorial cichlid, the situation becomes even more challenging. Both fish will compete for limited territory, which will inevitably lead to aggression and stress. For such a combination, the absolute minimum, in my opinion, would be a tank in the range of 150-180 gallons (approx. 570-680 liters), with plenty of hiding spots and powerful filtration.

In a 55-gallon tank, you could consider many other, equally interesting cichlid species that would feel comfortable in that volume. Keeping such large fish in too small a tank is unfortunately a recipe for problems.

Wishing you good luck and sound decisions!

 

[CeruleanRosee]

Hi,

I hope you don't take my comments as criticism, but I'd like to share my experience. Unfortunately, a 55-gallon tank (around 208 liters) is definitely too little space even for a single adult Oscar. These beautiful fish grow to really considerable sizes, often exceeding 30 cm (around 12 inches), and they need a lot of swimming space and produce a significant amount of waste. In such a small tank, an adult Oscar will struggle, which can lead to health problems, deformities, and a shortened lifespan.

When it comes to pairing it with a Green Terror, which is also a large and territorial cichlid, the situation becomes even more challenging. Both fish will compete for limited territory, which will inevitably lead to aggression and stress. For such a combination, the absolute minimum, in my opinion, would be a tank in the range of 150-180 gallons (approx. 570-680 liters), with plenty of hiding spots and powerful filtration.

In a 55-gallon tank, you could consider many other, equally interesting cichlid species that would feel comfortable in that volume. Keeping such large fish in too small a tank is unfortunately a recipe for problems.

Wishing you good luck and sound decisions!

How about african cichlids?

 

[tlindsey]

I have a 42×12×18 aquarium (length, breadth, height). This is my first time getting a tank of this size and I was thinking of keeping a few monster fish in it.

I really like Oscars and my friend suggested that I could keep gts with them. I wanted to cross check whether that is true. Please help.

Welcome aboard

 

[tlindsey]

How about african cichlids?

You could easily do Mbuna in a 55gal but do thorough research before attempting to keep them.

 

[Ancistrus Fan]

Do you know your water parameters? Green terrors and Oscar’s like soft to neutral whereas African cichlids like hard water. I have a 48 gallon which is the same width and length as your 55 gallon and I have a keyhole cichlid in there and plan for more. They are peaceful fish that get to around 10cm, they like to be in groups and would be a perfect option for your tank if your water parameters are correct for them. Africans can work in a 55 gallon, are you interested in mbuna or tanganika?

 

[duanes]

Agree with the above. To keep even 1 oscar alone, I consider a 6ft tank minimal.
And I know many people think because a GTs and Os both come from S America, they should be able to cohabitate. But GTs (from west of the Andes) and Os from east of the Andes mountains come from vastly different water parameters , and territorially complex attitudial worlds, Os come from varied cichlid communities, and GTs from places where the are the only cichlid in theiir habitat for miles..

And yes if you are selective you could make that size tank work for certain Africans, but not just randomly tossing species together.

 

[Cal Amari]

According to the tank calculator he's got a 40 gallon tank, not a 55

 

[jjohnwm]

According to the tank calculator he's got a 40 gallon tank, not a 55

Lol, that is not sweetening the pot at all...

"42x12x18 aquarium" and "monster fish" don't belong in the same thread...even before we get to that frighteningly descriptive "a few...".

 

[CeruleanRosee]

Lol, that is not sweetening the pot at all...

"42x12x18 aquarium" and "monster fish" don't belong in the same thread...even before we get to that frighteningly descriptive "a few...".

I'm relatively new to this hobby and I'm basically clueless about fish and their needs. I've made an aqua scape but it only has a betta sorority and a few nano fish.

I made this post just so I could cross check whether it was possible or not.

My apologies.