I was thinking about this. She's starting to be a bit of a chaser. If it continues she will be rehomed.Rivulatus, I'd be worried about the geos safety. Ofc this may not be a concern if the tank is large enough, setup to allow a spawning site and a safe refuge for the other tank mates.
The tank is a 6x2x2 (180 gallons) Some of the fish are red head tapajos,Deamons,Altifrons.To be honest hers and the males aggression will increase exponentially but without trying it there's no way of knowing how bad the scenario will become. What size is the aquarium? and any chance of a lot full tank shot?
Thank you for the words of wisdom. I was thinking the exact same thing with the Rivulatus. I really like the males. I will probably give the female away. I'm thinking of keeping just the male and see how he does with the group. You're right about being a disaster to see the others suffer and die because of my experiment. Believe me I would not go in that direction. I've been rasing these guys for almost 2 years.And Hoplarchus psittacus I wouldn't suggest allowing the pair to form. The other stock is far too delicate in my opinion. I also believe long term the male terror won't work unless you happen to have an exceptionally calm one (this is without the added problems of a pair). Spawning is almost a certainty, having experienced grow outs breeding at just over 2.5". Although while they remain small you may get away with it, the future doesn't look promising.
Setting out with failure on the horizon is not something to do. I would suggest maybe moving the Andinoacara on.
The current species all grow to be stunning adults and it would be disaster to lose their beauty and or lives. How many of them do you have? From you're pictures once they attain full size the aquarium will look pretty well stocked. There are many options for additional stock. I've always been fond of Panaque nigrolineatus which in my opinion would make an excellent addition.