Red Devil with Oscar?

[One_Phat_Pleco]

Hello! I had recently added a baby oscar to my 90G tank with some Yellow Lab cichlids and a Red Devil cichlid. Is it possible for these fish to be compatible?

Water Quality

Nitrate-40ppm
Nitrate-0ppm
Hardness-150ppm
Chlorine-0ppm
Alkalinity-60ppm
pH-7.2

The tank also has two Emperor 400 H.O.B. filters and a Marineland C-530 canister filter. There is also a 8in Bala shark and two 4-5 inch plecos.

 

[Colin_T]

While the red devil and Oscar won't mind the hardness of your water, the electric yellows come from water that is much harder and more alkaline than your water. Electric yellows come from the Rift Lakes in Africa and the general hardness is over 350ppm and the pH is over 8.5.

Oscars and red devil cichlids are Central/ South American and come from much softer water with a neutral to slightly acid pH.

There is also a big difference in size when the fish mature with the electric yellows reaching about 5 inches and the Oscar and red devil reaching more than 12 inches long.

Finally, temperament wise, the red devil could kill all the fish in the tank. The Oscar is relatively peaceful as are the electric yellows.

 

[One_Phat_Pleco]

Ok! Still though, my Red Devil is very nice ( just ate 1 baby Yellow Lab when I cleaned the tank once ) and never really got aggressive. He/she only got mad when its feeding time and it chases all the other fish away to get ALL of the food ( it doesn't do this anymore I now feed from 2 sides ). There is also a Green Banded Sevrum in the tank. Should I be worried about anything else? I do use buffers and cichlid lake salt when I do my water changes.

 

[Colin_T]

Severums are peaceful and not an issue but you need to increase the general hardness for the electric yellows long term health.