brown on live rock

helpme74

Member
Hello
I have a 75 gal reef ready tank. 80 lbs of live sand. With a 15 gal sump. I also have the following items heater, hot magnum 350 canister filters, AquaC Remora skimmer. I started my tank up about two weeks ago. I just added 60 lbs of cured live rock last week. This week I started to notice my live rock turning brown is this normal? The tank has no living animals in it.
 
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