The Fish Guru

Green Star Polyp: The Perfect Coral for Novice Aquarists

Green Star Polyp: A Complete Guide to its Care and Habits

If you’re into marine life and aquariums, you must have heard about Green Star Polyp (GSP), a fantastic, vibrant, and easy-to-care-for soft coral. Originating from the Indo-Pacific region, this beautiful coral is among the most eye-catching specimens in the aquarium trade, proving an excellent addition to both novice and experienced aquarists.

In this article, we will provide you with a complete guide to taking care of GSP, beginning with its origin and how it got its name.

Origin and Naming

Green Star Polyp, also known as GSP or Pachyclavularia violacea, is a species of soft coral that belongs to the family of Clavulariidae. In its natural habitat, the coral thrives in shallow reefs, in locations favoring fringing and barrier reefs in the Indo-Pacific region.

The coral’s scientific name, Pachyclavularia violacea, reflects its unique skeleton, which is heavy and somewhat brittle, causing it to snap under pressure. The common name, Green Star Polyp, is derived from its appearance, featuring dark green circular shapes shaped like stars.

The polyps in GSP’s colony have eight fingers, which extend from the center via a graceful curve. They also have a white center, which contrasts beautifully with the dark green tentacles, giving them an overall striking appearance.


In the Indo-Pacific region, Green Star Polyp thrives in shallow waters, where it attaches to firm substrates, such as dead coral, rocks, and shells. The coral’s habitat is around fringing and barrier reefs where the substrate is ideally flat and stable.

Even though the soft coral lives in the shallows, it can withstand current flow, allowing it to spread along the substrate.

Taxonomy and Naming

The Green Star Polyp’s taxonomy is as follows:

Kingdom: Animalia

Phylum: Cnidaria

Class: Anthozoa

Order: Alcyonacea

Family: Clavulariidae

Genus: Pachyclavularia

Species: violacea

The species name, ‘violacea,’ is derived from the color of GSP’s whiteness in contrast to its dark green tentacles. The scientific name ‘Pachyclavularia’ is made up of two Greek words, “pachy,” meaning ‘thick,’ and “clavularia,” translated as ‘club-shaped,’ describing the coral’s thick yet tender appearance.

Green Star Polyp Care

Green Star Polyp is a hardy and easy-to-care-for coral, making it perfect for novice aquarists. The coral is naturally resistant to many of the ailments that typically affect other corals and is relatively hardy to changes in temperature and water parameters.

Here are a few tips for keeping your GSP colony looking healthy:

1. Tank Size and Placement

Green Star Polyp thrives in tanks with good flow and bright lighting.

Medium to high flow water circulation is recommended, as it helps to circulate oxygen and nutrients to the coral’s tissues, aiding in their growth. Also, placing the coral in a bright spot, either mid- to the top-level of your aquarium, aids in its photosynthesis.

Tank size is not much of an issue since GSP growth is relatively slow. 2.

Water Quality

Green Star Polyp thrives in a stable alkaline environment, which encourages tissue growth. The pH level should be around 8.1 – 8.4, while the specific gravity should range around 1.023 – 1.025.

Ammonia and Nitrite should be ZERO, while nitrates should be below 5 ppm. Keeping an eye on water parameters is essential as fluctuations could cause trouble.

3. Feeding

Green Star Polyp is a photosynthetic coral and doesn’t require much feeding.

You can add marine snow, and a few feedings during the week are enough to help the colony gro and stay healthy. 4.


GSP requires moderate to strong LED lights to facilitate growth by providing enough nourishment through photosynthesis. Light intensities can vary slightly depending on the tank depth.

However, the typical range is from 100-250 PARs.


Green Star Polyp is a vibrant coral that adds life to any aquarium setup. With little to no feeding, an excellent habitat, and high resistance to common ailments, it’s an ideal addition to your tank.

As an aquarist, you need to ensure that the tank’s water parameters are maintained and that the coral receives bright lighting in a stable environment for continued growth. With the tips above, you’ll find keeping Green Star Polyp easy and even more rewarding.

Appearance and


Physical Appearance

Green Star Polyp is a visually striking coral that’s renowned for its beautiful radial tentacles. The tentacles, which are usually two to three inches in length, come in a brilliant neon green that contrasts against a white center.

Polyps in the colony vary in size, with taller polyps in the center of colonies surrounded by smaller ones. The tentacles end in rounded tips with an elongated appearance.

Under the right lighting, Green Star Polyp appears vibrant and fluorescent, giving a vivid, almost surreal look to the aquarium.


Apart from the typical green tentacle and white center, Green Star Polyp has several color variations. These color variations come in exciting hues of blue, orange, purple, and red.

The variations are due to differences in the polyps’ pigments, while the white center remains prevalent, setting it apart from similar corals. The branching variety of Green Star Polyp makes an excellent addition to any tank, with branched tentacles that create a different look.

Branching GSP is more challenging to locate than the regular GSP, but it’s entirely worth the effort.

Placement in the Aquarium

Best Environment

Green Star Polyp requires optimal conditions for healthy growth and reproduction. Being a soft coral, GSP requires moderate to high flow, which supplies plenty of food and nutrients, causing it to thrive.

In their natural habitat, GSP colonies spread outwards, ‘competing’ for space and light with other corals. This behavior makes them suitable for reef aquariums, where they act as indicators of appropriate water flow and nutrient conditions.

Water Flow and Lighting Requirements

Ideal lighting conditions for GSP are at least 6,000 – 10,000 K Bulbs with a PAR rating of 100-250. GSP will grow in low lighting, but it will grow slowly.

High-intensity reef lighting encourages the polyps to extend and reach out further, making them look more intricate. Additionally, GSP thrives in moderate to high flow conditions, considerably increasing their growth rate.

Placement Options

Green Star Polyp is adaptable and can be placed in numerous positions within the aquarium. The bottom and back of the reef tank are common choices as they simulate natural conditions, providing the water flow and lighting conditions required for growth.

They can also be located on rocks and substrates, producing unique shapes and textures. Placing GSP away from other corals is always advisable.

Even though GSP isn’t aggressive and doesn’t show signs of being territorial, other corals with more significant tentacles, such as zoanthids, may take over GSP’s area.


Green Star Polyp is an adaptable and hardy coral that presents visually stunning radial tentacles. The coral thrives in moderate to high flow conditions, and reef lighting is essential for growth.

GSP can be located either in the bottom and back of the reef tank or on rocks and substrates. Its neon-green tentacles and white center make it an excellent addition to any aquarium setup, creating a vivid and surreal effect that is hard to match by other corals.

Temperament and Toxicity

Reactions with Other Corals

Green Star Polyps are relatively peaceful and won’t harm other corals grown in proximity. However, they reproduce fast and can easily overtake other corals.

The coral is highly invasive and can cause problems for hobbyists keeping other corals that aren’t as aggressive. Additionally, GSP can grow over the top of other corals, limiting access to light and nutrient availability, negatively impacting their growth.

Toxicity Beliefs

Over the years, concerns have arisen about the toxicity of green star polyps. However, these concerns are often unfounded.

GSP’s solitary nature makes it less likely to cause harm to tank inhabitants, and there is no scientific evidence to suggest that they excrete any toxic chemicals. Additionally, GSP is in the Anthozoa family, and unlike their relatives such as anemones and jellyfish, they do not have stinging cells.

Care and Maintenance

Green Star Polyps are relatively easy to maintain, and they do not require any specific attention. But, like any other coral, it does require optimal water conditions to survive.

Water quality is critical, and regular testing should be carried out to monitor levels of nitrates, pH levels, and other parameters, ensuring that they remain within aceptable range. Regular water changes of up to 15% every two weeks or 5% per week are advisable.

Additionally, GSP being an invasive coral makes it necessary to prune it occasionally to keep its growth at a manageable rate. Trimming of excess offshoots should be done regularly to prevent it from outcompeting other corals in the aquarium.



Green Star Polyps are generally peaceful creatures and can comfortably coexist with most other reef inhabitants. However, they can quickly overgrow other corals in the tank.

They should be monitored and trimmed regularly to ensure their growth is controlled and not infiltrating other corals’ spaces. Green Star Polyps work best with other aggressive corals and tend to struggle with more delicate and non-aggressive corals.

Reef-Safe Fish

Green Star Polyps’ compatibility extends to its tankmates, including fish. Various species of fish have been known to coexist well with GSP, including species like clownfish, tangs, angels, and triggers.

These fishes are reef-safe and can live peacefully in a tank with Green Star Polyps. Clownfish, in particular, makes a good companion due to their ability to swim in and out of the polyps while also providing them with food scraps.

Finally, it’s important to note that fishes get along well with coral when their swimming and feeding habits are analyzed and tested. Feeding your fish with suitable food that won’t pollute the Green Star Polyp’s waters is crucial, as is observing your fishes closely in case they exhibit signs of feeding aggression.


Green Star Polyps are generally a peaceful and enjoyable addition to a reef aquarium setup. Their fast growth and invasive nature require periodic pruning to manage growth and avoid overgrowth of other corals in the ecosystem.

Green Star Polyps work best with other aggressive coral species and reef-safe fishes that are fed with suitable food that doesn’t pollute their waters. Proper care and maintenance of the aquarium with frequent water changes, monitoring water parameters, regular testing, and cleaning are essential, ensuring that the polyps remain healthy and thriving.

Propagation and Growth


Green Star Polyps are incredibly easy to propagate and spread, making them ideal candidates for aquaculture. The process of reproducing GSP involves fragging, where a piece of another colony is used to start a new one.

When fragging, it is essential to cut at the correct location so that you don’t damage the live tissues. You will need to select healthy branches from the colony and cut a small piece of the coral.

This should then be superglued to a frag plug for initial growth.

Initial Growth

Initially, GSP fragments will need to be placed on a frag plug or in sand with adequate nutrient availability to facilitate growth. Once the fragments have adequate nutrient levels and lighting, they will begin to grow in size, producing new polyps and branches.

If adequately maintained, the fragment will develop into a GSP colony, which can be transplanted into the main tank for continued growth. Green Star Polyps do not have high nutrient requirements, as they generally feed through photosynthesis.

However, they can benefit from the occasional addition of supplements like calcium, magnesium, iron, and others. They also require good water quality and stable water parameters for optimal growth and reproduction.

Closing Thoughts

Pros and Cons

Green Star Polyps present gardeners with both advantages and disadvantages. On the positive end, they have vibrant colors, are easy to care for, and grow relatively fast.

They are also ideal for novice aquarists, as they present an easy option to establish a healthy marine aquarium setup. However, one of the downsides of Green Star Polyps is their highly-invasive nature, which may cause them to encroach on other corals in the tank without any warning.

Additionally, once established, Green Star Polyps can be challenging to remove from the tank, particularly when using glues and adhesives. It’s vital to maintain this coral for proper growth and avoid overgrowth.

Beginner Coral

Green Star Polyps are an excellent pick for beginner aquarists due to their low care requirements and easy-care demands. They do not require any specialized feeding or attention, and their exceptional hardiness ensures they remain healthy in a variety of conditions.

They are an excellent choice for anyone looking for a vibrant coral to liven up their tank’s aesthetics without having to worry about complex care requirements and challenging maintenance schedules. In conclusion, Green Star Polyps remain a popular choice for more experienced and novice aquarists due to their low care requirements and the visual beauty they provide.

On the downside, their invasive nature requires careful monitoring to ensure other corals aren’t affected, and their removal might become difficult once they’re established. The ease with which they can be propagated makes them ideal for marine aquaculture.

However, like with any other coral, proper care, and maintenance is essential for them to grow optimally. With these factors considered, Green Star Polyps provide an ideal pick for anyone looking to add a visually-pleasing coral to their marine aquarium setup.

Green Star Polyp is a beautiful and easy-to-care-for soft coral that adds vibrant colors to aquarium settings. This coral is native to the Indo-Pacific region and has a unique appearance that’s characterized by radial tentacles with neon green variations.

Green Star Polyps thrive in moderate to high flow conditions and bright reef lighting. They coexist well with most fish and other aggressive coral species.

Additionally, GSP is easy to propagate, making it an excellent choice for marine aquaculture. However, hobbyists should pay close attention to their invasive nature so they don’t outgrow other corals in their tank.

In summary, Green Star Polyp remains an ideal choice for novice aquarists due to its low care requirements, hardiness, and attractive vibrant colors.

Popular Posts