A 135 gal cube would be 32x32x32
That's not a standard size so would need to be custom built. The depth would make it harder to light. The 32" length would require custom stands, hoods, etc and limit your lighting choice (e,g, couldn't use standard 36", 48", 72" fixtures.
Unless this is going to be in the middle of a room the 32 inch front to back wouldn't "show" as nicely as a more traditional shape. For example these three tanks would also be 135 gallons:
48 X 24 X 28
60 X 22 X 25
72 X 18 X 25
I think a 4, 5 or 6 foot long tank with angels would look more attractive than a 32 inch long tank and would probably cost less.
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Honda VF700S