Live Sand ?

I picked up a bucket of sand from someone in centerville one time.  Once I got home and took the lid off the stench was so horrific I didn't dare use it in my tank.  I rinsed and rinsed and could not get the smell to go away.  I wouldn't do it.  I've always wondered about the bags in LFS though, good question.

If this is for a small tank, don't use it. Consider LS as alive as a fish or a coral. You wouldn't be able to put them in the cold winter garage for a week and expect them to still be alive. There is a tip about this in the Reefkeeping Tips below.

It would be okay as just a small percentage of a larger body of LS, but if it has turned black or it smells bad, I would rinse it completely in freshwater before use.

Regarding the bags in the LFS, I have nothing but respect for CaribSea, but a cup or two of LS from a healthy tank has more life in it than a bag of AragAlive sand. And further, the only life in that bag is some bacteria that has mostly gone dormant from lack of food and flow. It takes a week or more for it to come back.