What should I add to my aquarium?

[sim1]

I was looking to add a bit more activity in the tank. At the moment the acaras sort of just sit there acting like angelfish and the Firemouth is nice but it looks bored.
Tank is 130L, 90Omm.

At the moment the current stocking is: 2x Electric Blue Acaras
1x Firemouth
1x Spotted Raphael Catfish
2x Siamese Algae Eaters
2x Sterbai Corydoras

Algae eaters will be taken out. I was thinking of adding congo tetras? Or another acara? another Firemouth? There used to be a smaller convict cichlid in there trying to breed with the Firemouth but the Firemouth started chasing it to the point where the convict hid behind the filter so I'm not sure about adding another Firemouth or another cichlid? There seems to be absolutely no issues with the Acaras however. I'm open to all suggestions, I live in Australia.

 

[Lcc86]

What's your water parameters, this may help people make suggestions?

Your Raphael (and algae eaters but i see you're moving them out) can grow to about 5/6 inches so maybe consider moving that out as well. Cories need bigger numbers, minimum 6 is recommended so that would be the first thing I'd do. Sterbais are really nice to look at so it's a win win getting more of them.

I don't keep cichlids but from what I understand the firemouth has potential to outgrow the tank too and are a bit more aggressive than acaras so that might be a suggestion for why the acaras aren't as active?