2 years ago
Last edited at 10:05PM on 3/18/2012
An oscar will grow over 10 times the size of the gouramis. The oscar will eat them as soon as he is big enough to capture them.
Now for the size of the tank, a 10 gal tank will only big good for a very very small oscar and it will quickly outgrow the tank. I have a 30 gallon tank. My oscar grew from approximately 2" in diameter to larger than my hand within about a year and a half. It stayed at that size for a few years before it became sick. The tank was too small for it.
Oscars are best kept as a single or pair of oscars. Anything smaller in the tank can and will be eaten by them.
You could put the fish together but it would not be advisable to so. This could impair their growth pattern since they would fight for food. They may even die not from lack of enough food only but also from injuries caused by themselves.