Hey. I now have a 60x18x20 tank, which everyone has referred to as 100 gallons. I even came across a TOTM saying it is 100 gals (http://www.thereeftank.com/totm/apr03.htm). But if you multiply LxWxH / 231, you get 93.5 gals. Am I missing something? Or is it just a weird size with a weird volume?