I had a chip on the edge of the glass pictured in my mind. There are two options I would consider and unfortunately leaving it as is isn't one of them. First you could simply replace the tank, left as is I think that at some point the tank will fail. It could always be transformed into a terrarium or something like that. The second option is dependant on whether you could place the chipped side towards the back (this obviously won't work on a tank viewed from both sides), since it is a glass tank and silicone adheres well to glass as long as its cleaned properly you could make a patch out of a 6-8 inch square piece of glass (I would use 3/16" or 1/4" thick) and silicone it in place so the chip is centered in the patch. This will work out aesthetically only if the patch can be hid by your aquascaping or if you added a false wall on this inside of the tank.
If you still have the chip you could try the windshield repair kit like already mentioned but I don't think it will work in this situation.