Star Polyps

Care

Star Polyps are attractive,fast-spreading corals that are easy to keep in the home aquarium. The polyps typically have a light-coloured centre with tentacles that may be any shade of brown, green, or yellow, and arise from a mat-like, low-growing base. The base may be beige, brown, purple, or red in colour and the polyps can extend upwards for a distance equal to that of their diameter. Belonging to the Pachyclavularia genus, the growth form of Star Polyps is very similar to that of Clavularia (ClovePolyps), however there are slight differences. In Pachyclavularia, the flat stolon mats are quite rubbery in texture and less fibrous compared to those of Clavularia, a result of irregularly layered stolons. The polyps that emerge from the stolons are completely retractile, but much less featherlike in appearance, lacking the lush pinnules that are so typical of Clavularia. Instead, they have 8 thin, smooth tentacles that form a star shape surrounding the polyp centre/oral opening, which is often a contrasting colour. In the wild, Star Polyps grow on shallow, inshore reefs and reef flats where there is fairly brisk water movement. They are usually very hardy in the home aquarium, but will require strong lighting and decent current if they are to thrive; like many species, they are prone to detritus collection and filamentous algae growths if the water flow around them is not turbulent enough. Likewise, lighting must be bright enough for them to produce sufficient zooxanthellae, as they are poorly equipped for prey capture and also lackwell-developed means of digestion. Due to their colonial nature, Star Polypswill spread to adjacent live rock very easily, forming a lush carpet, so plenty of room for growth; although they do not possess any significant numbers of tentacular nematocysts, they can easily overgrow neighbouring corals. The best position for Star Polyps is somewhere that you can control their growth if necessary, such as an isolated rock formation/island on the sand, from which they cannot escape. Given the chance, they will colonise the back wall of the aquarium, which can look very attractive as the mass of polyps undulate in the current. From here they are not difficult to control as it is easy to scrap the mat off of smooth surfaces. Unlike many of the Clavularia species, Pachyclavulariacorals can be stung, so avoid placing them too near potent stingers as otherwise they will refrain from opening their polyps. The nuisance anemone Aiptasia likes to try and settle amongst any slight gaps in the mat, so observe carefully to ensure that they do not manage to work their way in, taking hold and adversely affecting the colony by causing degeneration of the mat. Most reef fish and predatory invertebrates tend to leave Pachyclavularia spp. alone; this is thought to be due to the significant level of terpenoid and diterpenoid compounds that they produce, which seem to act as a deterrent to most predators. However, there are one or two exceptions, and we would recommend that you avoid housing these corals together with shrimps from the Lysmata and Saron genera, as these have been known to prey on and cause some damage to Star Polyps. The actual status of many of the Pachyclavularia species is actually in quite a degree of disarray. The bright green variant that many are familiar with, and which you may see labelled as Green Star Polyps or GSPs, are often erroneously referred to as "Clavularia viridis" - this is an old misnomer, and whilst many now attribute the name Pachyclavularia violacea to this species, this is also invalid and so GSPs should simply be referred to as "Pachyclavulariasp." until further taxonomic studies are carried out. Some experts believe that a number of the Pachyclavularia species actually belong in the genus Briareum; whereas others argue that they do not fall neatly into any particular genus. Please be aware that Pachyclavularia spp.can be sensitive to some phosphate removers that contain aluminium oxide.

Feeding

This is a zooxanthellate species that requires good lighting to sustain the photosynthetic algae living symbiotically within its cells. Some experts believe that it may also benefit from the absorption of micro-particles from the water, so additional feeding with microscopic foodstuffs such as plankton and foods for filter-feeding invertebrates could be advantageous.

Propagation

Very easy "simply allow to spread to surrounding pieces of rockwork. Daughter polyps are produced from the edge of the stolons.