So here's the way I think It can work. Make two pieces of acrylic angles. Silicone them over the front and back of the top of tank. Let dry two days. Install clamp in the center pull snug place two new acrylic braces across tank and weld to the new front and back let sit for a couple days. Cut old center brace out carefully remove clamp. Pray I don't have 180 gallons of water in my living room!