lava rock in reef tank?

I have some small pieces of red lava rock that I would like to add it to my filter, but is it safe?
Some say it is harmless. and some say not to use it.
I would like everybody’s opinion. should I use it or not?

 

Nope metal leaching = bad.

 

I have used it in freshwater tanks for years and never had any problems, but from what I have heard it isnt the best stuff to use. I would be worried about using in a SW setup knowing what I do now.

 

lava rock contains metals that will leach out. can be highly toxic.

do not use lava rock in a reef tank.

 

Since SW is more caustic than fresh it may cause silicates and heavy metals to leach plus nothing will colonize it because of the rough edges. So no go for SW.

 

I don't understand what you mean by that. Can you/someone please elaborate?

 

I think they mean peanut worms, spaghetti worms, and other larger life forms. Bacteria would surely colonize it which is all you need for it to be considered live rock.