Would this myth depend on WHERE the plant was located?Myth #1 - You can put any kind of plant into a riparium with good results.
Not true! The best kinds of plants to keep in ripariums are those that are adapted to grow in the natural shoreline environment. While the banks or rivers, lakes and streams often have abundant water, sunlight and nutrients, they also pose speial problems for growing plants. A very important limiting factor for plants growing in this kind of habitat is oxygen availability around their roots. The amount of oxygen dissolved in water is limited to begin with, and where there is substantial bacterial activity (as there often is in nutrient-rich muddy sediments) it is further deprived. Plants that are evolved grow in wet marginal areas can thrive in these sorts of conditions, but most other plants will quickly suffer root death and perish if planted into a shoreline habitat, or a riparium planter.
Furthermore, plants that are evolved to grow in deserts, treetops, forests or vegetable gardens will also make a very poor representation of the riparian habitat. Don't you want your riparium to be realistic? There are hundreds of fascinating and beautiful plants that can grow in the shoreline environment--most of the underwater plants that we keep in aquariums can also grow as marginal emergent--so it is a much better idea to select among these when planning a riparium layout. You will have mcuh better results growing the plants and your setup will look much more like a real shoreline area in nature.
Eg, in many paludariums, there are upland regions where non submersed tolerant plants can be placed in soil. Tillandsia species are intolerant, but are often planted. It does not imply that the plants cannot be used at all.