Live Rock

[hnf2k]

i went with everyones suggestion, i bought 200 pounds of live rock...my salinity isn't really stable, the numbers keep changing, so is it still ok to have the live rock in my tank if my salinity isn't at what it should be yet? and also do i need to keep my lights on for the live rock, even though my tank is all cloudy?

 

[a&m aggie 04']

i know you hate hearing all these, "you should haves" but i think it would have been better to wait until your tank clears to put the rock in. You'll just have to blow the sand residue off the rock with a powerhead now.
Your salinity is going to continue to go up until all that salt is dissolved. Dont know anyone that has ever done it that way so im not sure what effects it will have. If im correct invertebrates are very sensitive to salinity. With constant changes of your salinity you might kill any hitchhikers you have.
Live rock doesnt need any special lighting to survive.
Someone correct me if im wrong, but I think fish are the only things that can withstand salinity changes. Thats why you can use hyposalinity on them.

 

[hnf2k]

so are you saying my live rock is all gonna die?

 

[azrile]

What do you man by not stable?
is it 1.021 today, 1.022 yesterday. 1.021 the day before that?
Or is it rising very quickly
As long as it is within 1.020-1.024 and stays in that range, you shouldn't kill the live rock.

 

[broomer5]

HNF2K
Most anything we put in our marine tanks appreciate a stable salinity of around 35 ppt of salt/minerals.
A specific gravity range between 1.022 and 1.026 is pretty common for home tanks.
The animals, plants and bacteria that live in our tanks normally do best if we keep the salinity similar to what they've evolved or were designed to live in.
Have you tried siphoning out a volume of water and sand from your sandbed ?
You could start the siphon hose in the top of your tankwater siphoning water into a large bucket. Once you have the siphon started, place your thumb over the end of the tubing in the tank.
Then stick it down into the bottom of your sandbed, all the way down to the bottom of your tank. Let off your thumb and pull some water/sand from the bottom of your tank to a SEPARATE plastic container or small bucket.
Suck out some of this sand/water from the bottom of the tank into this other plastic container, enough to fill your swing arm hydrometer, then place your thumb back over the inlet of the tubing. Keep your thumb over the end and remove the tubing from the tank.
Don't let the tankwater in the upper parts of your tank "contaminate" the water/sand that you've pulled out from the bottom of the tank.
Let the sand settle out to the bottom of this container, then decant the clear water to your hydrometer and take a reading of it's specfic gravity.
Compare the specific gravity of the water from your sandbed water to the specific gravity of the water in the upper/mid levels of your tank.
This may tell you if the dry saltmix that was originally placed down under the sand has dissolved uniformly in your tank, or if the sandbed water is super saline, still containing water that has a high concentration of undissolved salt in it still.
I would confirm that the saltwater has a somewhat consistant salinity before adding any living things to the tank - live rock included.
If the specific gravity is uniform thoughout your tank, then I would proceed with adding the live rock.
200 lbs of live rock is worth taking a few extra precautions in my opinion.