OK, I went back and did the math. In rough numbers it's 1/4" glass and 18+ gallons.
I've never worked with or heard of Crystal Glass, but I'm assuming it's an equivelant of Starphire which is a low-iron glass, which is known to be scratch-prone.
Having said all of the above, my only concern for the scratch would be that it takes a whack of some sort from either a decoration, pump, stone, etc. which would cause it to run edge-to-edge. At that volume I would be less fearful the panel flexing under pressure and bringing on the same result. Think of it this way: when you score one side of glass to cut it, and rap the bottom of the score with the ball end of the cutter it's done with the desired purpose of making the score run and split along its' length.
But again, there are absolutely no rules or timetables for this stuff. Just reasonable precautions.