Well...4' in the wild is a bit exaggerated. They grow more around 3'+ In captivity, you're looking more around an average of 18"-24" Feeding can be tricky if it's the only tank inhabitant. Congrats on getting it to accept cooked shrimp. I'd leave the tail on. Nothing wrong with feeding it the tail. Remember that variety is the key. Pellets, fillets of fish, shellfish, etc.