So I have been keeping fish for quite a while, and never really thought seriously about having a planted aquarium, as plastic is easier... Well, I would like to know what some of you think would be the right way to start a planted aquarium, but in an existing setup. Do I need a different substrate (have gravel now)? I know I will probably have to get rid of the fish that I currently have which are known to eat plants, but other than that, it cant be as easy as putting the plant in the gravel and just letting it grow. Is it?