Uberhoust
Fish Herder
30 X 12 is just like lumber. In the US and Canada you can buy 2" by 4" (2x4s) but in reality they are 1.75" x 3.5". The tops are designed to fit the inner space on the tanks, unfortunately each manufacturer is different. Also some manufacturers tops don't fit their tanks. For example I have a top fin 37 gallon tank which is supposed to fit a top fin 12 x 30 tank yet in top fin's case the top is actually 0.125" too wide. Cutting a wide strip of glass is pretty easy, cutting an 1/8" off is pretty hard without a diamond saw.
