Red Tail Shark The red tail shark is an active scavenger in the aquarium and is very easy to keep. These "sharks" are actually catfish and will eat anything they can fit in their mouths - which are fortunately small. Red tail sharks only grow to about four inches. The shark pictured is show quality, few red tail sharks get color that deep. Scientific name: Epalzeorhynchus bicolor Shipping Size: Approx. 2 inches