can I put rocks that I got from the ocean in my tropical fish tank???

[PeeTee]

It will take a very long soak(and many water changes) to get the salt out of the rocks,then try boiling them to kill off the live stuff that may be there,then OK.
Generally speaking,preparing things that you find to put in your tank requires more effort than it's worth. But it certainly is do-able.

[stephen G]

In the summer I got some rocks at Narragansett beach in rode island over the summer. they look so nice so i wanted to put them in there. is it ok to. or is it bad to??? will it harm the fish?