You will see them, they usually don't hide if maintained in well equilibrated group. They are very good swimmers. I kept the furcatus, one of the most beautiful and interesting behaviours of the family I think. I sold them because I had only a 60gal (120cm long). I think they will show their potential only in +150cm long tanks. If you see them in 100-120 gal tanks, you'll understand what I say
If you unstock your tank, you could try them for a while to decide by yorself
Something important, they won't live long in acidic soft water like your other fish, but they will still spawn if maintained in specific