The stand is very nice looking, however you must keep in mind that it will need to hold about 800 pounds. Using a DIY that you have no specs on is just risky. If it fails, you'll likely be out more in damages and loss than what it would have cost to buy a suitable stand.
If you do decide to go against logic (no offense) I would consider some way to add some cross supports to help distribute the weight, but even that probably won't be enough. Do you know what size tank was on it before?