The stand looks nice but the structural part of it is not what I would consider to be strong or safe by any means. Personally I would not feel comfortable putting thousands of dollars into a tank on top of a stand like this. To me it doesn't look like it was built by someone who deals with aquariums on a regular basis. First, oak is much more expensive then 2x4's so to think that they were using that material to try to save money can't be the reason. Second, they didn't do it that way to save space because a 180 stand is plenty big inside. It almost looks like they didn't know any better. Third, the fact that the sides are only sitting on half of the bottom board is reducing the weight distribution of the sides by half and putting more stress on the side walls of your stand. Fourth, a custom stand shouldn't have flake board as the bottom.
Looking at a stand and assessing it for strength is one thing, actually putting over a thousand pounds of weight on it is another. And then expecting it to stay stable and hold for years to come is something totally and completely different. I don't know what you paid for it but its nothing compared to what you're going to spend on top and inside of it. Definitely add some supports in it. And call and complain...you should have them fix it or get a partial refund. Good luck!
