Scientific Name: Briareum sp (used to be classified as Clavularia viridis)
Common Name: Star Polyps.
Type of Coral: Softie
Lighting: Moderate and Moderate to Low
Flow: Moderate and Moderate to Low
Care Level: Easy
Temperament: Peaceful
Appearance
Star Polyps are a smaller coral having a height of about ½ to 1 inch and a head size of about ¼ to ½ inch. The heads of these corals can completely retract into the base making it look like a think purple coating on your rocks. Green and pink are the more common color to find this coral in. I have read they can be found in other colors, but I have only seen them in green and pink.
Water Conditions
The below link highlights typical water conditions star polyps will require. I have had the best luck when they were kept in water with 1 to 2 ppm of nitrate when lighting and flow requirements were met and all other water parameters in line as described in the below link.
https://www.reefaquarium.com/2013/the-basics-of-marine-aquarium-water-parameters/
General Information
Star polyps are colonial type corals, meaning they form a colony of many individual polyps all connected together. As they do not have a calcified skeleton structure, they can be more tolerant of swings in the alkalinity, calcium, and magnesium when compared to other corals. However, they will not be very tolerant to swings in pH, Temp, or salinity which is no different than any other coral or fish..
Star polyps are a very hardy soft coral placing them amount the easier to keep corals and making them an excellent choice as corals for beginners. They have also been known to grow very fast, almost like an invasive coral. These corals can grow on your rocks, on the substrate, and on the glass of your aquarium. They grow almost like a carpet of small polyps. Star polyps are also the least aggressive when it comes to defensive abilities. They can quite frequently become damaged and even start losing heads when they fall victim to another coral’s sting or exposed to those toxins.
As with all corals, the exterior slime coating can be a skin irritant or even highly toxic to humans so please, handle all corals with care. I would recommend wearing rubber glove whenever you handle corals
Fragging
Star polyps can be easily fragged with very high success