Glass V.S. Acrylic V.S. Starfire Glass Aquarium Materials by Lev Ingman

There are a few differences between glass and acrylic.

Glass:

Glass weighs a lot more than acrylic and it generally does not scratch as easily, but it can crack and shatter if it is not perfectly level on its stand. Also, if there is an earthquake, chances are that your glass tank will shatter. You cannot lift a glass tank with anything in it because the bottom may shatter. Sometimes larger glass tanks can withstand an earthquake, but be aware that you should always know that it could crack. Glass tanks usually also have corners that are glued(with Silicon usually) together whereas Acrylic tanks often come with rounded edges. Glass tanks also often times have a top and bottom rim for added support whereas Acrylic tanks are usually rimless. You can also order your glass tanks to come with black silicon and diamond cut corner edges to make it look nicer.

Acrylic:

Acrylic weighs a lot less than glass, and it will not generally crack or shatter. The only downsides are that acrylic will scratch easily and it will cost twice as much. Acrylic is also ~20% clearer than glass, which makes the tank look better. If you are going to be careful about not scratching your tank, then acrylic is the way to go, but be warned that it is very difficult to find an acrylic tank that is not scratched up. Acrylic tanks are also usually rimless and come with nice rounded corners. 

Starfire glass:

This type of glass gives you the added ~20% visibility that you get with acrylic but it does not scratch as easily. The cost is about the same as acrylic, but you still need to make sure that the stand is level. You can order your tank to have only starfire front or starfire front and side panels to reduce the total cost because it does not matter what the back and bottom panels are made of. Larger glass tanks seem to withstand earthquakes a lot better than smaller glass tanks.

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