unclenedsfishfactory.com

conversion tables
volume in gallons...
fun math stuff like that

http://www.petfish.net/calculators/calculate.php

note:
a lot of my customers do not know
how many gallons is in their tank or pond

this is of particular importance if you should ever need to medicate

basically there is about 2.45 gallons in a cubic foot

so a 15 gallon tank is 2 foot X 1 foot X 1 foot
(length times width times height times 7.45 equals gallons)