I would like to have my tank planted with java moss and java ferns. My substrate will not have much gravel (maybe 1/4 - 1/2 inch) so i need a plant i can attach to rocks and driftwood(i will have many chucks of wood in the tank). So i came to the conclussion of java plants. First off, will goldfish eat them? Second, how do you attach java ferns to plants and rocks. I know java moss is tied using fishing line but i imagine java ferns have roots?

And finally, how do you go about finding java moss. It seems to be a popular plant but i never really see it at any lfs.
Any tips or comments would be appreciated considering i've never attempted a plants tank before.
Thanks