The seal is supposed to be translucent, but its turning white as if air is getting into it. It looks as if more and more air is slowly getting in, so slowly what's left of the translucent silicone, is turning white. I don't see ant bubbles getting into the tank, but with a 110 gallon fish tank, I don't want to take any chances. None of the other corners are currently turning white only the one. I cant figure out how to insert pictures on here, but if you left my your email, I could send you some. PLEASE HELP IF THIS TANK FALLS APART, I LOOSE ABOUT $1000.00 THANK YOU