haha, see i was right i think i should get some rep points for thatAs long as the sand is moist.Or maybe a centimeter of water over the sand, it will be fine.
You will get die off as you will be mixing the different bacteria that live at the different depths in the sand.
Remember different bacteria live in different layers of the sand, the deeper the sand less o2.
Warr - Yes - there would be SOME die-off. But not too much. Please let us know what you planning to do with the sand?
Perhaps you should let the sand "cycle" in a seperate container with a power-head only (and sea-water) for at least 2 weeks before you place this sand in your tank/sump......
Unless you are planning to start a brand new tank - then just let the sand cycle in the new tank without adding new life..... you are bound to have ammonia/nitrite spikes still....