Redoing my tank

[mrtian97]

I am redoing my 5 yrs old reef due to need to move for redoing the floor.
My rocks are fused with the sand that are calcified, how to loosen the rock so I can remove, should I just pour vinegar in the tank to dissolve?
Thanks

 

[lapin]

I would remove as much water because the vinegar will kill off bacteria on the rock. Toss the sand and get new