Fish tanks do not need complete support. It was proven to me about 30 years ago using all different sizes and configurations of tanks including my own of 8' in length. Most of the weight settles on the ends of the length, and the way this was proven to me was by running a busness card underneath several tanks on stands, shelves and then some just supported on each end by cinder blocks. My own 8' tank was placed on cinder blocks on each end, filled and enjoyed for about 5 years until I gave it away. The folks I gave it to, used the same cinder blocks and as far as I know still have it set up that way.
It was explained to me that the actual weight of the water makes the bottom bow up slightly in the center, therefore no center support is necessary. Although this was proven to me, and although I used that huge tank for years with no center support, I still prefer something on the order of full support throughout even if the tank doesn't touch it. I guess even with proof, I'm skeptical. Additionally, a bowfront may respond differently.
It was explained to me that the actual weight of the water makes the bottom bow up slightly in the center, therefore no center support is necessary. Although this was proven to me, and although I used that huge tank for years with no center support, I still prefer something on the order of full support throughout even if the tank doesn't touch it. I guess even with proof, I'm skeptical. Additionally, a bowfront may respond differently.
