Mixing a gar with an Arowana?

Which Gar and which Arowana?
 
Both fish will get too large for the tank.
 
A florida gar would probably be fine in a 180g, which dimension 180 is it? most floridas don't get much over 12" in captivity, thoguh some will get to 18". You would need a tank with a 3' width ideally. A silver aro will get way too large for a 180g.
 
A florida gar would probably be fine in a 180g, which dimension 180 is it? most floridas don't get much over 12" in captivity, thoguh some will get to 18". You would need a tank with a 3' width ideally. A silver aro will get way too large for a 180g.

the tank is 6 foot by 2 by 2.

Are there any arowanas that could fit into my 180?
 
no. too expound. most primitive fish do not have the flexibility to turn in a tank that is less than their body length. Even the smaller aros (blacks) will get 2-3'and just would nto do well in your tank for life.
 
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