Oi...
I dunno. I suppose you could use clear silicone to patch the chip back in spot (for aesthetics only though), and maybe some kind of Eurobracing perhaps on the inside.
If you intend to have sand in the tank, you could put a small patch of glass over the spot, at least the sand would cover it.
I hate to say this but I would have avoided a bent glass tank for exactly this reason, you can't replace just one panel. I'm surprised you can even get a tank with bent glass like that, it's quite a different beast than just a curve like a bowfront. That's a single point of failure for 3 sides. Sorry, I know I'm just pouring salt in your wound now ... you have my deepest sympathies. I would *totally* be going after the movers for a replacement cost on this one.
Best of luck, whatever you decide.