mine was soo small when i got him.. he was all silver as well. now he is 14-15" and very colorful with jet black fins. i got him to eat pellets right away, crickets, and freeze dried krill.
iono i give him my koi pellets but he doesnt seem to eat it.... he will put it in his mouth and spit it back out... what kinda pellets do arowanas like..??