Well I thought I had a 55 gallon tank or at least 50... but I used the calculator and the INside measurements and came up with about 46 gallons... So am I wrong to guess that's supposed to be a 50 gal tank? I know this has probably been discussed before but I'm having a hard time searching for it. When they sell you a tank at a store and say it's so many gallons, is it really? I'm sure this is a standard size tank but I need to find a cover for it... it has a center brace so when you look at the top there are two sections... Basically thought I need a cover well suited for some non-aquatic critters that would be able to find their way out if there is one. I went to petco the other day and the only thing they had the size I needed was a glass top for almost 50 dollars... not only is that a lot of money but I need something that I can not only put my light on but has adequate ventilation... I have considered making something myself but to make it functional and halfway decent to look at is probably more trouble than I want right now... I really need to set the tank up soon though... any thoughts...?