I have heard that Arowana and Discus Fish can't live together. I tried at my home and They are living happily. There is no fight between them.... Discus fish are one of the most popular fresh water aquarium fish But if you are I have a new 125 liter aquarium 803550 cm and would like to know if I can have Arowana fish also known as dragon fish are large eye-catching fish which have relatively long life spans of up to 20 years These fish are primitive thought Discus Fish is one of the most popular fishes to breed Discus fish when bred nicely results in lots of rewarding time spent watching these types of fish swim close Dec 16 2009nbsp018332Best Answer The Silver Arowana will get over 25ft long you need a tank at least 4ft wide for a silver yes thats more of a pond so Feb 12