In that first picture.. I have the same stand. It fits a 50g, 55g, or 75g. I have my 75g on it. I have maybe a half inch left of stand with the width of the 75g. the width of yours on that stand sure looks like a 55g.
I wanted to leave a lip on the front side of the tank so that if needed i could place cups and what not on it.. The tank does hang off a couple inches but i have a tiny *stand" made out of particle board and two by fours between the black stand and the wall to support the rest of the tank and to also leave room to hide my airpump so its not just sitting on the side. The stand was a hand me down and I had to make an add on to gwt what I wanted :/
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