Adding live rock to existing system

[Chago09]

Do you think that adding 10 lbs of live rock to a 150 gallon will cause a cycle???? I know it may cause a small one although it won't be anything that can harm my fish will it???

[WinnipegDragon]

Why not cure it outside the tank first?

[enemec1]

I added about 6lbs to my 210 system no side effects caused. from what I under stand small amounts over a long period of time. If you can try to get LR from some one breaking down rather than the fish store. I did it this way in my 75 gallon where I added around 50lbs to the 100lbs that were in the tank. again no side effects.

[garyw68]

I have added 10lbs to my 90 with no spike.

[pezcubano]

I agree with Enemec. I just picked up a used tank and I kept his sump water, algae, and substrate alive while I moved the tank. I added around 75lbs of LR and my levels haven't budged.
I would buy a good load of base rock and some cured rock to go on top. I've gone 50/50 on my purchases of LR and Base Rock.
If you are setting up your tank you might as well buy everything at once and let the tank cycle...
If you want to add later, once there are fish in the tank, you will have to do so little by little.