My 200 g glass tank had a chip like that (I found out when I was carrying it and cut my hand). I just glued mine back in place with silicone. No problems for the past year.
My 270g has three chips in it. I filled the chips with silicone (its in the fishroom so it doen't have to look perfect) and has held water with no leaks for the past 5 years (combined previous owner and me). Got the tank for $200 because everyone else was afraid of possible leaks.
I would just epoxy the acrylic (like has already been said) and don't worry, be happy.