I have 5 redhead tapajos with rotty juvies at the mo, I think they'll all get on fine and dandy
There are sooooo many lovely geophagus out there, ask around and see what you can get hold of!
Make sure you ask what they can get for you too, as they are geo's you'll want a group of approx 5, an LFS is more likely to get fish in for you in numbers like that...