You can never have to much biological filtration. After saying that, Live Rock is excellent filter media and as far as risks are concerned, Anytime you introduce something into your tank there is a possibility of something unwanted being there. This includes fish and plants 
If the live rock is dead and cured then it will become alive again over time, If it is ready to go "live" with your NO bulbs anything that requires bright light will die off. I am talking about hitchhiker corals and such, not bacteria or some algae.
Jim
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90 Gallon glass, 135#'s of rock and 2" sand. 2-250w 20k XM metal halides. 2-95 watt actinic VHO, 4 powerheads, Coralife skimmer. Maroon Gold Striped Clown, Blue Chromis, Kole Tang, Pygmy Angel, Serpent Star, Brittle Star,Gorgonians, Mushrooms, Yellow Polyps, Turbo Snails & Blue Legged Hermits. 20 gal sump with Caulerpa, Mag 7 return pump. |