Do you not have any saltwater at all? Because the best way to keep it alive is put it in a Rubbermaid/bucket submerged in saltwater and a pump moving it. If you can't do that then you can wrap it in wet (with saltwater) news papers and put it in a Rubbermaid/box with a lid. Or worst case scenario you do not have any saltwater at all then unfortunately you rock is drying off which is going to cause some die off. You can put the rock in a sealed box if it is wet and hope it stays moist but I feel you will still start the long cycle.