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Saltwater Aquarium Algae

A saltwater aquarium is for keeping marine plants, animals. The algae in such aquariums are termed as saltwater aquarium algae.
Ningthoujam Sandhyarani
Though the basic maintenance tips for freshwater and saltwater aquarium are more or less similar, the latter type requires extra equipment and strict monitoring of water quality. In addition, the marine plants and animals are more expensive and hard to preserve.
In order to regulate a stable environment, large saltwater aquariums are usually preferred. Many hobbyists prefer to maintain them, as marine plants and animals are fascinating and spectacular.
The classification is based on the temperature condition of the tank (tropical and temperate) and the type of inhabitants. Depending upon the inhabitants or organisms, it can be only fish, fish with live rock, and coral reef aquarium.
Various algae are also added to enhance the aesthetic value and maintain the water quality. Some of the commonly used ones are given here.


Most of them belong to the Chlorophyta (green) and Rhodophyta (red) division.
The green ones are beneficial, rarely cause nuisance in the tank, and grow easily, while the red ones require very clean water for growth. They should be pruned regularly. Following are some species that can be used.


Caulerpa is the most popular green algae used. In total, there are about 75 species of Caulerpa. The structure consists of a stolon with rhizoid-like roots and blade-like fronds.
The color of the fronds may vary from lime green to bluish brown. Caulerpa act as filters and remove excess ammonia, nitrates, and phosphates from the marine exhibit. They also harbor various microfauna that are consumed by other inhabitants.


The distinctive feature of Halameda is the chain of circular plates arranged end to end. They secrete calcium carbonate in the tissues. For it's optimum growth, there must be enough amount of light and calcium in the fishbowl. They are not tolerant to excess nitrates and phosphates; hence, they are often used as indicators of a healthy aquarium environment.


Commonly known as bubble algae or sea grapes, Valonia resembles a cluster of bubbles. Very often, its spores are introduced in the tank through the rocks. They are deep green in color and soft to touch. Proper pruning is necessary to avoid uncontrolled growth and overtaking of coralline.

Encrusting coralline

Encrusting coralline, belonging to Rhodophyta, are found in several colors like white, pink, purple, red, and green. Similar to corals, they secrete hard calcareous shells; hence, they are named as coralline. By growing coralline of variant colors, you can create a beautiful color pattern.
Unlike other types, encrusting coralline are difficult to establish and should be grown under optimum light conditions.
Algal growth in a saltwater aquarium is usually seen even without introducing them. If not controlled properly, the excess growth can damage the aquatic museum by rapidly altering the water chemistry and affecting the inhabitants.
One of the most common examples is the diatom that appears brown in color. If left untreated, it will develop on the tank walls, rocks, and other exposed surfaces. Effective elimination can be done by using specific media that remove phosphates and silicates.