Bowing acrylic 75 aquarium

[mannyfresh78]

Is it normal for an acrylic aquarium to bow a bit from the front when you fill it with water???? I'm worried?? It's NOT NEW, it's used. But it was cared for no deep scratches or no cracks. I'm thinking its 1/4 inch un-level. Meaning it leans a tad forward so I was going to add 4 shingles to bottom stand to level.

 

[Timfish]

Standard sized acrylic tanks typically will have a small amount of bowing.