Combing two tanks? Is this scenario possible

[Ramona_boner]

So my partner and I had a falling out about 2 months ago. We had fallen victim to the 'aquarium phase' in life and had ended up with at least $1000 worth of fish and equipment..
During our separation I upgraded tanks - to a 4x1.5x2 ft tank. Due to some losses, I ended up with a baby oscar, convict, upside cat (her prize fish) 6 silver dollars.

My partner has kept our 30cm ghost knife, as well as our school of clown loaches (approx 10), pair of angel fish and squeaker sailfin catfish..
The tank she has is not as big as mine.

We think we should swap and change some fish around, like move the ghost knife to my big tank, as well as some of the loaches.. but we're not sure about where to keep the baby oscar and the convict .. As they can be aggressive fish and they are much smaller than the ghost knife..

What are some other fish keepers suggestions?

I know there were some rookie mistakes made with planning co habitation of species but were trying to do the best for them now?

 

[Wiggles24]

I honestly don't find oscars to be very aggressive at all, convicts on the other hand are the nastiest fish I have ever encountered.

 

[dwayne.aycock]

I hear a major problem when it comes to water conditions and what the fish will need to thrive.
The Angels and silver dollars are South Americans and will benefit from a planted tank with soft water and an acidic PH (somewhere around 6.5-6.8).

The clown loaches are Asians and can get along with the South Americans, as the Angels and Silver Dollars don't tend to be aggressive. They love frozen foods particularly brine shrimp and blood worms.

The Ghost knife can go with the Angels and Silver Dollars, but is a top to mid level feeder so a floating pellet that sinks slowly may be a good idea.

The rest of your assortment is a toss up. They may or may not get along, but at least they wont kill the other fish. If they are small, one day they will grow up. Oscars are known for their appetites, and can make a meal of the other fish. The Convict will become territorial, so having lots of plants or places to hide may help with this issue. The Convict will pick on the other fish, but is the Oscar is similar in size, it should be able to hold it's own with the Convict. I would NOT add any other fish to this mix unless you are thinking of tetras to go with the South Americans. Just avoid fin nippers. Anything added to the tank with the Oscar and Convict will become a meal.
Good luck!
D