I'm not sure what you will learn by looking at photos (not that looking at photos isn't fun on its own)... those three tank sizes have different footprints, and will look roughly the same from the front.
Figure out how much space you have, how much money you have, and get the largest one you can fit and afford. It's great that 125 is your bottom end tank... that's a great size to start with. But if you can fit a 6x2 foot tank or 7x2 (or 8x2!), then definitely go with that.
Stands are easier to find and thus easier to afford for a 6 foot tank, which may be a consideration, so keep that in mind, but if you can find or make a bigger stand then by all means, get the biggest one.
And then post the pictures for us to see!
Here's mine. It's a 6x1.5 footprint (same as the 125) because that's the largest dresser I could find and it's in the bedroom. I wish I could've gotten a 180 though. The fish would be much happier.


Figure out how much space you have, how much money you have, and get the largest one you can fit and afford. It's great that 125 is your bottom end tank... that's a great size to start with. But if you can fit a 6x2 foot tank or 7x2 (or 8x2!), then definitely go with that.
Stands are easier to find and thus easier to afford for a 6 foot tank, which may be a consideration, so keep that in mind, but if you can find or make a bigger stand then by all means, get the biggest one.
And then post the pictures for us to see!
Here's mine. It's a 6x1.5 footprint (same as the 125) because that's the largest dresser I could find and it's in the bedroom. I wish I could've gotten a 180 though. The fish would be much happier.




