Hi, I have a tank with the following dimensions: Height 12 1/2 inches Width 18 1/2 inches and Depth (front to back) 9 1/2 inches. How many gallons is this tank? Sorry but my math is poor. Thanks in advance.

Here is a great link to do it for you http://www.geocities.com/dick_pahimulin/tools/vcalc.htm

I came up with 9.5 gallons, so it is probably a ten gallon tank. :-)

Thanks! That's a very helpful link you sent!

you can actually type it directly into google. an example would be
"20cm x 30cm x 30cm in us gallons" and then push search. it'll calculate it for you. I just typed this, "12.5 inches x 18.5 inches x 9.5 inches in us gallons" and it gave me this "(12.5 inches) x (18.5 inches) x (9.5 inches) = 9.51028135 US gallons" so gallons work too.

Awesome, I never knew you could do that with google nor could I find a decent website that would do all the calculations for me before!

This is a good link too

http://www.ifocas.fsworld.co.uk/calculator.htm