Category: Caulerpa

This species features long, dark green, fronds with segmented appendages. Its very similar to Caulerpa mexicana, but it’s fronds are spaced further apart and have a more uniform, tapered shape. It is also much more tolerant to a wide range of temperatures and a voracious grower in both the aquarium and in its natural environment. For this reason it is the single most controversial species of Caulerpa, as it can quickly take over non-native, nutrient rich waters if introduced. Today, it is rarely seen in the United States due to its recent addition to the Federal Noxious Weed List and infiltration of non-local waters. It is currently illegal to ship or transport this particular algae from any location and possession is banned in the state of California. Despite its reputation, there are many aquarium strains still in propagation in aquariums throughout North America, as well as Europe and Asia. It has been reported to grow occasionally in Florida waters, but has not been a problem due to the abundance of competing algae. Not palatable to fish or invertebrates.

Scientific Name: Caulerpa taxifolia

Common Name: Fern Algae

Origin: Mediterranean, Caribbean

Depth Collected: 4-40 Feet

Maximum Height : 10″

Growth Rate: Fast

Light: Moderate

Temperature: 60-84

Propagation: Fragmentation, Sporulation

Difficulty: Easy

Food Value: Not Palatable

Nutrient Uptake: Excellent

Flow Rate: Low to Moderate

They’re many subspecies and variations of Caulerpa racemosa found worldwide. This species of racemosa is unique in that it has perfectly round individual clusters, resembling grapes on a vine. Like most species of racemosa, individual plants can quickly outgrow the available nutrients in a tank, so care must be taken to limit the size of each specimen. It grows in the inter-tidal zone in fairly shallow water and depends upon moderate to high currents to supply the essential nutrients required for growth. It should be closely monitored in the aquarium, as its well known for dying and releasing reproductive spores in captivity. Overall it’s a very hardy macroalgae that does very well in the marine aquarium.

Scientific Name: Caulerpa racemosa 

Common Name: Grape Caulerpa, Sea Grapes

Origin: Gulf of Mexico, Caribbean, Brazil

Depth Collected: 2-50 Feet

Maximum Height : 8″

Growth Rate: Fast

Light: Moderate to High

Temperature: 72-86

Propagation: Fragmentation, Sporulation

Difficulty: Easy

Food Value: Somewhat Palatable

Nutrient Uptake: Excellent

Flow Rate: Moderate to High

By far the most popular and widely distributed species of Caulerpa available for use in the aquarium. This species features dark green, slender, oval shaped blades attached to a single rhizome. It often has new growth that appears on old blades which is true to its name. Depending on the environment provided, it can grow very wide blades (up to 1″) in turbulent areas and grows tall and thin in shallow, calm habitats. Individual blades are often spiral shaped when collected from shallow waters, especially when found in sea grass beds. Not very palatable to fish, but will be nipped at by some herbivores. It prefers to grow on sandy substrate, and once established, will quickly grow over the front of an aquarium.

Scientific Name: Caulerpa prolifera

Common Name:  Sea Blade Algae

Origin: Gulf of Mexico, Atlantic, Caribbean

Depth Collected: 4 – 30 Feet

Maximum Height : 6″

Growth Rate: Fast

Light: Moderate

Temperature: 76-86

Propagation: Fragmentation, sporulation

Difficulty: Easy

Food Value: Somewhat palatable

Nutrient Uptake: Excellent

Flow Rate: Low to Moderate

This species of Caulerpa features a thick rhizome, with compact clusters of rounded or flat topped uprights. This particular algae is usually found in low light habitats such as shaded seawalls, under ledges or in very deep water. In the aquarium it is an excellent nutrient consumer, so much so that it must be monitored so that it does not outgrow the available nutrients. It is highly variable in characteristics depending on where it is collected. There are two distinct varieties, although it is unsure if they’re separate species. One features smooth round caps, while the other has a more concave shape with thin edges. In shallow water, the uprights grow much taller, more closely resembling Caulerpa racemosa. Somewhat palatable to fish.

Scientific Name: Caulerpa var. peltata

Common Name: Saucer Algae, Mushroom Algae

Origin: Gulf of Mexico, Atlantic, Caribbean

Depth Collected: 3-200 Feet

Maximum Height : 6″

Growth Rate: Fast

Light: Moderate

Temperature: 72-86

Propagation: Fragmentation, Sporulation

Difficulty: Easy

Food Value: Somewhat Palatable

Nutrient Uptake: Excellent

Flow Rate: Moderate

Caulerpa paspaloides features palm shaped fronds that extend upward in clusters to form a symmetrical tip. This species is fast growing and very hardy in the marine aquarium. Under intense lighting it forms tight, dark green filaments that have a triangular appearance. Under most aquarium conditions however, the growth is much different and resembles individual feather shaped fronds with a light green appearance. A thick rhizome securely anchors the plant in mud and shallow turbulent environments. Because of its fine filaments it can accumulate sediment and diatom growth so it should be pruned from time to time. Simply pinching the rhizome and breaking off individual pieces is recommended. It’s not as palatable to fish as other species of Caulerpa.

Scientific Name: Caulerpa paspaloides

Common Name: Palm Tree Algae

Origin: Gulf of Mexico, Atlantic, Caribbean

Depth Collected: 5 -10 Feet

Maximum Height : 12″

Growth Rate: Moderate

Light: Moderate

Temperature: 78-86

Propagation: Fragmentation, sporulation

Difficulty: Easy

Food Value: Somewhat palatable.

Nutrient Uptake: Excellent

Flow Rate: Low to Moderate

Caulerpa mexicana has a deep green color with beautiful segmented fronds. It grows rather compact in turbulent environments, but can extend into larger leaflets up to 6″ tall in calmer conditions. Attaches with rhizomes to rocks, coral fragments as well as sandy and mud bottoms in shallow protected areas. This species is very adaptable in the amount of light it requires to grow and is often observed growing under ledges on seawalls and intertwined with other algae. There are several species of Caulerpa that are very similar in shape such as taxifolia and scalpelliformis, but they lack the tight segmented fronds and somewhat rounded tips characteristic of this macro algae. An excellent, hardy specimen for the marine aquarium. Most Caulerpa species are very palatable to fish and invertebrates.

Scientific Name: Caulerpa mexicana

Common Name: Fern Algae

Origin: Gulf of Mexico, Atlantic

Maximum Height : 8″

Growth Rate: Moderate

Light: Moderate

Temperature: 78-84

Propagation: Fragmentation, sporulation

Difficulty: Easy

Food Value: Somewhat palatable to fish

Nutrient Uptake: Good

Flow Rate: Low to Moderate

A very popular species of Caulerpa for refugiums and or display in the marine aquarium. It features long, erect, feather shaped blades that form a somewhat rounded tip. The coloration varies, but is typically a light green shade. This species grows very quickly and can be problematic in some reef aquaria, as it can quickly take over the aquascape. It’s palatable to many fish and inverts, so is an excellent choice as a food source because of it’s fast growth. It prefers to grow on rocks and hard surfaces rather than sand, but it’s quite adaptable to grow in almost any environment. It has an interesting habit of climbing up the sides of an aquarium and rocks as a vine would. Sertulariodes is one of only a few species of Caulerpa that typically grows close to shore, but can be found growing sparsely to depths of about 50ft.

Scientific Name: Caulerpa sertulariodes

Common Name: Feather Algae, Fern Algae

Origin: Gulf of Mexico, Atlantic, Caribbean

Depth Collected: 5 -20 Feet

Maximum Height : 8″

Growth Rate: Fast

Light: Moderate

Temperature: 78-86

Propagation: Fragmentation, sporulation

Difficulty: Easy

Food Value: Palatable to both fish and invertebrates

Nutrient Uptake: Excellent

Flow Rate: Low to Moderate

This species of Caulerpa features small, irregular branched uprights with a series of flat serrated blades. It’s a Pacific species that made it’s way into the United States through tropical fish importers. It’s currently much harder to find due to stricter import regulations with Caulerpa species, especially in California. Its native to shallow water habitats, growing on small rocks and coral fragments. This smaller sized specimen is very hardy and will not grow too large in the aquarium. It’s somewhat palatable but it is mostly left alone due to its stiff composition.

Scientific Name: Caulerpa serrulata

Common Name: Sawtooth Algae

Origin: Indo Pacific, Asia

Depth Collected: 1-15 Feet

Maximum Height : 5″

Growth Rate: Moderate

Light: Moderate

Temperature: 78-86

Propagation: Fragmentation, Sporulation

Difficulty: Easy

Food Value: Somewhat Palatable

Nutrient Uptake: Good

Flow Rate: Low to Moderate

This species of Caulerpa features long, stiff, uprights with finger-like clusters of notched blades attached from a long rhizome. It is typically found growing intertwined with sea grass beds, channels and ledges in shallow water habitats to about 10ft deep. When found in deeper habitats it’s growth is much smaller and stunted. This species of Caulerpa prefers sandy substrate, but will attach to rocks and coral fragments. It is very hardy in the aquarium and is relatively undemanding in its needs. All Caulerpa species should be pruned back to encourage new growth and to prevent die off in the aquarium. It can be safely buried in the sand bed or left to attach on their own as they grow. Not palatable to fish and invertebrates.

Scientific Name: Caulerpa cupressoides

Common Name: Zipper Algae

Origin: Atlantic, Caribbean

Depth Collected: 1-15 Feet

Maximum Height : 8″

Growth Rate: Slow

Light: Moderate to High

Temperature: 74-86

Propagation: Fragmentation, Sporulation

Difficulty: Easy

Food Value: Not Palatable

Nutrient Uptake: Fair

Flow Rate: Moderate

They’re many species of Caulerpa racemosa found worldwide. They can be highly variable in composition, which makes it difficult to properly identify each individual species without inspection of the cell structure under a microscope. This particular species of racemosa features a dark green color with tall branches composed of long clusters of cylindrical shaped fronds. It resembles a bunch of bananas and is very attractive in the marine aquarium. Like most varieties of Caulerpa racemosa, it can quickly outgrow the available nutrients in a tank, so care must be taken to limit the size of each specimen by regular division of the rhizome. This species is not very palatable to most fish and invertebrates, although some algae eating fish will nip at the rhizome structure.

Scientific Name: Caulerpa racemosa var. cylindracea

Common Name: Banana Algae, Grape Caulerpa

Origin: Gulf of Mexico, Caribbean

Depth Collected: 4-25 Feet

Maximum Height : 6″

Growth Rate: Fast

Light: Moderate to High

Temperature: 72-86

Propagation: Fragmentation, Sporulation

Difficulty: Easy

Food Value: Not Very Palatable