Something doesn't jive here.
In one sentence you say you want to move everything to a QT tank.
In another sentence you say there is nothing in the tank.
Which is it?
If the "everything" you refer to moving is Live Rock and/or Live Sand and you plan on moving it back after the water change, then I would do a 50% water change....but then....why move "everything" in the first place?
Just some thoughts.
Cheers
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