Surface area - more important than volume?

If you have the standard goldfish bowl, and you fill it halfway with water, Imo, you could keep a lot more fish in there as opposed to filling it to the brim, cause half full, will have less water, but provides more surface "oxygen" exchange area.... Are we in agreement???

 

to an extent, but if u fill it more there would be more water in the bowl and more water means the fish would have more oxygen stored in a greater volume of water, if that makes sense, if u agitate the surface then it would make a difference and a larger surface area would be better, but goldfish bowls are banned now arent they?

 

Nope!

It is better to have a wider tank, rather than a deeper tank of the same volume, but to have a tank half filled does not mean you can keep more fish in it, compared to the same tank being full, just because it has the same surface area for less water volume.

You still need a certain volume of water to sustain the fish in good health.

EDIT: Sorry, thinking I'm not quite understanding? Are you asking specific to a goldfish bowl where the top is narrower than the middle?

To answer that, yes you would have more surface area, and therefore more oxygen exchange, but the loss in water volume would outway these benefits. This is why Goldfish Bowls should be outlawed as cruel, as they are firstly badly designed in terms of oxygen requirements, but also, they are far too small for their intended use... Keeping Goldfish!

Just my thoughts!
G!

 

I think that agitating the water is the key factor.
It promotes gas exchange and also increases the surface area.
Without agitating a surface film will form that will hinder gas exchange.

 

Source: http://en.wikipedia.org/wiki/Aquarium

But on the other hand having a larger volume of water means fish waste and other pollutants gets diluted faster so I guess you need a good balance between enough volume and surface area.