Using Local Lava Rock

[Cruiser]

I was wondering if I could use some locally gathered lava rock (in my fish only tank) with some live rock that I purchased. The goal is to get the stuff growing/living on the live rock to spread over to the lava rock. I have been given mixed advice on this. One person says it is fine and a good, inexpensive way to get lots of live rock and another says the lava will have lots of heavy metals that will harm the fish. Any suggestions? Thanks
Cruiser

 

[reefrunner69]

says the lava will have lots of heavy metals that will harm the fish

I agree with this statement to an extent. I think Lava Rock can contain many elements and minerals that can adversly effect the inhabitants of your tank and your water chemistry. The keyword is "can", I have seen it used many times with no problems and just as many times with disaster, it's hit or miss IMO.