i try to know which plants are truly submersible and which ones are actually bog plants, but sometimes there's too many names to remember! so a rule of thumb i stick to is this: if a plant has stiff stems or leaves that look like they can support themselves out of the water, its more likely a bog plant. if a plant has flimsy looking leaves or stems that can sway easily in the water column, then it is most likely a submersible plant. im sure there are exceptions to this rule, such as anubias, which are a bog plant genus but can still do fine underwater. but i find out that this rule applies to most plants.