Green Star Polyps

Green Star Polyps - Metallic

Green Star Polyps are a common coral for beginners and still one of my personal favorites.  This coral encrusts to rock (or anything else it can touch) and once a large colony is established it resembles a wavy phosphorescent field of grass. The bright green splash of color waving in the current is a beautiful addition to the reef aquarium.

While the disposition of this coral is considered peaceful it is important to know that the coral should be placed so that the growth of the coral can be easily managed.  This coral grows quickly and many reef tanks have been quickly over taken.  Placing the corals on small “islands” of rock in the tank will keep them from spreading out of control.

GSP placed on "islands" so they do not take over the tank.

Common Names: Green Star Polyps (“GSP”)

Skill Level: Beginner

Classification: Soft Coral

Disposition:  Peaceful

Light Level: Moderate to High

Water Flow: Strong

Disposition: Peaceful

Water Conditions: 72-78° F, dKH 8-12, pH 8.1-8.4, sg 1.023-1.025




General Placement example for Green Star Polyps per lighting and water flow


Star Polyps contain zooxanthellae within their bodies to provide for the majority of their nutritional requirements through photosynthesis.  This basically means that they have the ability to get their food from the lights on your tank.  They can also benefit from weekly feedings of foods specifically designed for filter feeding invertebrates but it is not necessary. However, you may notice from time to time that when feeding your fish the GSP will trap small pieces of food with their tentacles.

Green Star Polyps grow by spreading a purple encrusting mat.  You will notice that GSP are an excellent indicator to your water quality.  Notice that your GSP is not growing as quickly as it used to? Check your pH and Alkalinity.  If your coral stays retracted into the purple mat through the “daylight” it’s possible you do not have enough water flow on the coral.   Lift the coral in front of the power head and blow off any debris you notice on the purple mat. It’s also possible to clean off the mat with a toothbrush.  This coral needs high flow to keep the mat clean.

Purple GSP Mat

Propagation of this coral is very easy.  The Purple mat can be peeled off the rock and super glued to another rock.  I usually start the peeling process with a flat head screw driver pushing it between the matt and the rock. Then once I have the mat raised up I slowly peel it off the rock with my fingers.  Once you have your section of the mat pulled off, simply place a few dabs of superglue on the new rock and glue the mat down onto it. It’s okay to have your coral out of the water for several minutes.  Once the glue is dry place your rock back into the tank.  Give your coral several days before you see full polyp extension.

When shopping for GSP you will notice there are several different color variations available. Some of the more popular colors are Metallic Green (neon green color) and Winter Green (Dark Green but longer flowing tentacles).  There are many other shades ranging from green to brown. I have also seen for sale a sort of purplish white although I have never personally owned one. Care is generally the same for all the different colors. You should choose a color that appeals the most to you and enhances your tank.

Interested in buying a Metallic Green frag? Buy Metallic Green Star Polyp frag

Interested in buying a Winter Green frag? Buy Winter Green Star Polyp frag

More Information: Additional Green Star Polyp Information

Need a simple fragging Kit? View fragging kit on amazon


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