How did you find a tank that big?

I was trying to look up my tanks dimensions, and it kept seeming to small. So I fetched a yard stick and manually measured it, and it appears I have a 40, not a 30. I got it from my sister, I'd assume she'd know what she was doing, but apparently not. Not that I mind or anything, my tank just grew by 10 gallons after all lol.

So my tank at 36 x 16 x 17 is about half the size of yours, though a bit more wide and a touch less tall. Could it hold five adult females then?