Here's something I learned the hard way about basements. Many older unfinished basements were built unlevel to help with drainage. Pay extra attention to the levelness of the stand and tank. It gets tricky on unfinished concrete floors and you can start with what appears to be a level set up when empty but shifts when you add water, and then can shift again if you add any heavy stones or decorations.
Take the extra time to ensure the set up is level on uneven concrete floors. Big tanks will come apart at the joints in a matter of weeks.
Naldo