I'd fill it in with aquarium silicone and include a couple inches up and down... or just do that entire corner of the tank. Let it cure for 24-48 hours.. until you can't smell the vinegar-ish smell... then fill it up and test it.
Wait.. maybe scratch the above. I just looked at your pics again. Is the chip and pictures from the inside of the tank or outside? At first I thought the pictures were from the inside but the bottom picture looks like it's from the outside. If from the outside, is the black corner angle brace on the inside of the tank.... like a DIY repair for that broken corner? If they did it right, it should be OK from the inside but the chip on the outside, if hit again, could start to spider across the glass.. like a windshield in a car. I would look for some clear epoxy or a DIY auto-glass repair kit and use that *glue* to seal the chipped area so the liquid also gets into any small fissures and seals/glues them to make them less resistant to spidering across the glass... just like they do on repairing little chips in windshields. There's no guarantees though. If this is a back corner of the tank, you could use an outside black plastic corner angle and cover the corners with this to hopefully protect that area from getting hit again.
