Metynnis Maculatus (Spotted Silver Dollar)

[Tonym]

I have a Shoal of Metynnis Maculatus in with my Pike Cichlids in my 6ft. The two Pikes are fully grown at 8 inches and I am feeding them frozen Sand Lance as well Earth Worms. The Silver Dollars go mad for the Sand Lance and strip it to the bone very quickly like a Piranha (I know there related). Has any one else seen this behaviour from Silver Dollars.
 
Regards
 
Tony

 

[Goggy]

Its normal to have shoaling fish do this