Worried: big tank above garage..need ideas

[kaboom]

I have a bonus room over my garage that I want to add a freshwater tank. The biggest concern is the amount of weight it can support. What I have in mind is a tank around 180g (72x24x24) but not sure if that's too hefty?
The tank will be placed along the exterior wall in the bonus room where it lines up below (garage) along the same exterior wall. That supporting wall in the garage is unfinished and I can see 2x6 studs @16" on center. There is also a support beam right in the middle where the tank situated right above.
Here's an amatuer depiction of that.

Attachment 3361

Will this size tank and wall support work together? Am I over looking anything? Please reply if you have similar size tank on your main floor. Thanks.