I have a 90 gallon tank. I took a lot of risk in mixing fish people usually don't recommend and after trail and error I have american and african cichlids with a few oddball fish. I plan on buying a new tank within the year for the Pacu and Arrowanna to grow in and the Ornate Bichir when it gets larger also. I am looking for large unique fish to add to my collection. Or a really colorful or unique gentle giant. I try to add the kinds of fish that other very plain people don't usually own - or can't even keep because there tank isn't big enough. I want to WOW people when they see my tank. I want them to ask me: "What is that? That's so cool!" - I was wondering if I could mix in an African Lemon Cichlid with these others, or would it be too aggressive compared to my others?? 
I have:
One small Frontosa (C. sp. "North" Burundi Type)
Two small Rainbowfish
One almost medium Black Ghost Knife (unknown species)
Three adult Upside Down Catfish
One 1.5in Angelfish
One medium Blood Parrot Hybrid
One small Red Bellied Pacu
((And an Ornate Bichir and Arrowanna to come soon))

I have:
One small Frontosa (C. sp. "North" Burundi Type)
Two small Rainbowfish
One almost medium Black Ghost Knife (unknown species)
Three adult Upside Down Catfish
One 1.5in Angelfish
One medium Blood Parrot Hybrid
One small Red Bellied Pacu
((And an Ornate Bichir and Arrowanna to come soon))