Yes they keep slamming into the walls of the tank and land up with a flattened snout similar to shovel nose cats that end up with bent snouts. Placing fast swimming fish in square tanks unfortunately may result with that happening.In my experience the goliaths with a “flat” snout are the ones that are Skittish. It happens overtime after repeated pushing against the aquarium glass. I’m yet to see a wild Goliath (or any other tiger gush) with a flat snout.