I'm gonna have to disagree with mike. I see the leg he is talking about and its supported by another 2x4 on the end which would withstand the weight of the tank alone even without the other support there. I'm not saying it couldn't be the stand I just don't think that 1 2x4 caused that due to the fact the other 2x4 support in that area is flush with both top supports and could easily hold the weight in that corner.