Magnetic rock in my tank?

[Gordo124]

I think i may have put a magnetic rock in my fish tank... Its one of the rocks that i found laying around outside... Is that bad for the fish?
Cuz people use that magnetic glass cleaner ...

 

[squidsquiggle]

I'm not sure about it being magnetic, but I personally wouldn't put any rocks from outside in my tank unless I was sure I knew what they were (but then I am kind of paranoid). While not the most grammatically correct article, this is a really good basic list of safe and unsafe rocks for the aquarium. Hope that helps!