Introducing New used live rock??
 

What is the best way to introduce live rock from a private sale?

How much to what size system... Because no matter what there will be die off and slight cycle... i feel safe adding 5-10 pounds to my system (100G volume, 80lbs established LR).

Spread it over a few days and do water changes.. you could probably add a good chunk in..

I'd say it depends. I have moved live rock by transporting it in a rubbermaid type container in water for up to an hour and half and have had no cycle. I think as long as you keep it in water you will be good. It is when it is out of water for more than 5 or 10 minutes that you will start to get die off.

Thanks Ron, JD. How about when the system was taken down within a week or so ago, and with no lights but from the window? There was heat and water flow. There was part of a dead fish in the tank, but know smell whatso ever. The rocks didn't smell like amoina.

based on my experience I would recommend to check really careful for CRAB, I had to tare down my aquascape just to catch the hair meaty crab.