Sorry I don't understand by "gap"? The clamps just hold the glass square (90 degrees)Do you need a gap between the glass on builds this large? Is that what corner clamps do?
What gap? You talking about joint gap? This is something I have always been curious about. I would think to much silicone and it would flex to much. I know Miracles clamps all there tanks from front o back and alot of the tanks I have torn apart you can barley fit a razorSome bigger tanks have a 1/32-1/16 gap between panels which is supposed to be stronger