Let me be a bit pedantic here Craig. Although lots of tanks have been built that do not require a center support, when you see one on the original tank, it is required by the design. When you have a center brace it is because the tank designer decided that he/she could save a bit of cash on glass by simply supporting the middle of the glass span and using thinner glass. If you then remove that support, your only option would be a thicker glass that would resist bending by the force that the water exerts. I have a 6 foot long tank that a previous owner removed the center support. I DIY built a top frame that includes some top bracing because the tank without that bracing was bowing out over an inch in the middle at the top. That tank has 1/2 inch thick, 13 cm, glass in the front and back that most of us would not expect to see bend ever. I also have a tank that is only 4 feet long and had a broken center brace when I bought it. Before I added any water, I repaired that center brace so that it again can carry the force of the water against the glass. Ignoring the original design parameters of any tank is done at your own peril. I prefer to maintain the strength the original tank designer had intended.
