only use treated for the stand.
If you check out my 210g build thread you will see a plain 2x4 stand that is capable of 3k pounds, all the weight rests on the 2x4's
You dont need 4x4's to build a structurally secure stand.
My stand was built in a matter of 2 hours. I also have it filled and running for the first time today, and there are ZERO creaks and ZERO movement of the stand.
That's not a planted tank. That's a jungle with glass around it- MFDROOKIE Circa 2011