Considering on average a silver will reach 24" within it's first 2 years. You would need a minimum of a 6' x 2' x 2' tank(180 gallons). Eventually the silver aro will get well over 30" for this your looking at a 8' x 30" x 24" tank (300 gallons). Bigger is always better.
im going with the 240, thanks for the help i dont know what kind of aro i want yet, the only aro's my work we have are silver's and we had a jardini. i just have to see if he can special order me one i want.thanks again.
What are the dimensions of the 240g? Typically it is 96" x 24" x 24". Spend a little more and get a 300g wide the dimensions are 96" x 30" x 24". With the added 6" of width you could possibly keep a silver in that tank for life.