Plants comprise a major part of a fresh-water aquarium but are not really necessary in a marine aquarium. The addition of some lush green marine plants is a great temptation. This is fine at first but as the plants begin to deteriorate, as they almost always do, there will be some cleaning chores ahead. However, some types may thrive successfully for a period of time. Algal plants of the genus Caulerpa are now being used by many aquarists. Red or green plants are less likely to cause trouble than the brown ones. If you are collecting the plants yourself be careful not to damage the roots. If the plant is anchored to a rock, clip off the pieces of a rock with the roots attached. It is more apt to survive than if it is pulled off and replanted. use plants sparingly and watch them closely for signs of new growth, an assurance that they are thriving.
The proper amount of light is just as important as in freshwater plants. Too much light may cause unwanted algal growth, too little inhibits growth and the plants soon die. The actual light requirements are mostly unknown and must be determined by trial and error. At present marine plants are not recommended, at least until some experience is gained in caring for them in a tank separate from that in which the valuable fish is kept. The higher growing and larger plants look best at the back and sides, particularly grass-like plants and the long-stemmed plants like Cabomba. For those who insist on having more greenery in their aquaria artificial plastic marine plants are available. They are relatively inexpensive, replaceable, and can be removed periodically for cleaning. See to it that they are specifically designed for marine aquaria and constructed out of "safe" material. Some are plastic on wire and should not be used. For those decorations that are potentially dangerous but very attractive there is always the shadow-box for their placement.