I dont get it as far as I can see reptiledirect has the aquarium size and the dimension of the UTH on their website. I dont see how its there fault you ordered the wrong size? It says on their website that the 30-40g one is 11"x11" for the cobra brand. And the 30-40g for the repti brand is 14" by 8". Thats the only two brands I see on their website. Are you sure they sent you the right one or are they advertising different sizings then what they ship? Im wondering because I was about to make an order with them.