How Big For A Silver Dollar?

[CFC]

Silver dollars are extreemly skittish with virtually any fast movement from outside the tank causing them them to panic and hurtle around the tank causing the other fish to panic as well, definately not fish for a household with children or a tank placed in a high traffic area.

 

[Genesis]

my angel is a bottom dweller

 

[Genesis]

she always sits near the bottom, doesnt like the current near the top, does this mean i can put some SDs in? or will they still nip regardless?