How fast does live rock dry out?

So I put my sump together tonight and after I got all the rock in it and i got it going I realized I didnt have enough water and now the fish store is closed so i cant buy any pre mixed salt water to add and i have quite a bit of live rock in my sump that isnt under water. Will it be alright til tomorrow afternoon? If i have to i can make salt water here but it will be with tap water which i really dont want to do. What ya think?

 

IME
It will be OK until tomorrow providing you keep it damp

this could be achieved manually , basically using a jug and pour water from your sump over the expossed rock every couple of hours or so

or if you have a spare power head and a lenght of hosing -you could trickle water over the rock to keep it wet all the time until your level increases

better still - think bird that wanted to drink water from a beaker that it could not reach with its beak - it dropped stones in to raise the water level and thus was able to drink the water

you could increase your water level with tapwater - without affecting your salinity
by making a couple or as many as you need large bottles of tap water - with the caps on, add these to your sump and this will raise the water level in your sump
and the tap water is contained , these can then be taken out as you increase your water level with RODI mixed saltwater tomorrow

Steve

 

it should be ok till tomorrow afternoon. Id suggest u wet it frequently though every couple of hours to keep it moist. Or u may wanna cover it with a wet cloth soaked in the same saltwater that its in so it wont completely dry out.

As a matter of fact im in the exact same predicament right now, filling my new tank and about half the rock is above the water level.

 

Your a genius! Thats exactly what I will do =] Thank you