[gotseamonkey]

how long can live rock stay out of water? for i want to re arrange my set up but dont want bacteria to die off.

[Ninong]

It shouldn't be a question of how long live rock can stay out of water, it should be how can I rearrange my live rock without causing any harm to it.

Just get a cheapy plastic tub and put some of the tank water into it. You can buy these things for as little as seven or eight dollars. Just do a water change on your tank so that you end up with some of the tank water in the temporary holding container. Even if you have to use half new saltwater for this temporary holding tub, it would be better than using all new saltwater. You can then remove your live rock from the main aquarium and place it in this holding tub for a few hours if necessary without having to rush things.

On the other hand, to answer your original question, the bacteria in the live rock will survive for several days with the rock out of the water but other lifeforms on and inside the live rock will begin to die off as soon as the rock is out of the water. The longer it is out of the water, the more the die-off. Live rock can easily survive several hours, even a couple of days, out of the water with very little die-off. It all depends on what's on and in the rock to begin with.

P.S. -- You could even use one of those cheapy plastic tray looking things they sell at Wal-Mart to store blankets under your bed. They're about two feet wide by three feet long by about 10" high. That way you could spread out the live rock so that you would have easy access to the individual pieces.

If you think you can rearrange your rock in less than an hour, then maybe you could skip the part about filling the container with water and just use it to hold the wet rock so that you don't make a mess. It all depends on how long you think this is going to take and what sort of stuff you have on and inside your live rock.

[knutcracker]

yeah, the safest way is to have to them in water constantly. it's really not that much of an additional hassle, considering the amount the work it takes to re-work the LR. if you have corals, i would do the same and throw in a powerhead for some flow.

another important concern is the temperature once they (LR, corals) are out of the tank. i am not sure how low or high the temp can go. maybe ninong can clarify it for us.

[Ninong]

If your tank water is say 78 degrees Fahrenheit and your ambient room temperature is 72 degrees Fahrenheit, then there will be very little change in the water's temperature even if you don't use a heater. Besides, even if the water temp drops a few degrees, it won't hurt anything.

[knutcracker]

sorry to hijack the thread, but how low does the temperature have to get before bacteria starts to die off? and how long at that low temperature, thanks.

[Ninong]

I don't think you need to worry about bacteria dying off. Unless you decide to put your live rock in the freezer or in your oven. In other words, your water temperature isn't going to get low enough to cause your bacteria to die off.