Putting LR in there is ok...Of course they want you to buy all LR there since It is like what $7-9 lb..The more live rock you have your new tank will cycle and establish faster..The downside is that you may get pests inverts like coral eating crabs,coral eating nudibrachs, aiptasia and down right bad algae ...Cooking rock is usually putting Lr in freshwater like Gomer said or flat out letting the LR dry out and making sure most or all of these pests are dead before putting them in ur tank..You do not want want to put this rock in your display because if you killed it when you put it back in water the die off will give ammonia spikes and could kill your tank..placing it in a tub of fw or sw is fine until no die off (ie ammonia,nitrite)..starting off with clean base rock is great because you know what is on the rock ..Nothing!! just calcium carbonate...Most stores sell base rock much cheaper and Marcos rocks does this online..ANY rock placed in a tank will eventually become alive (microflora,bacterially)and grow coraline algae(purple rock)..SO yo do have options..You do not have to follow a prescribed method for keeping SW(exact LFS advice believe me when I started I was told MH would kill my coral , and adjusting /testing my diy ca. reactor was nonsense, and OZONE will burn down you house and may kill you if you breath it!!.you would not believe who told me all this!!)..Review RC you can spend an eternity on here believe me you will probably save time and $..If you need any questions answered on here you have many people with many years of experience willing give you mixed answers that generally follow the same consensus
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