Description
Care
Yellow Polyps are a popularchoice for the marine aquarist, although they are yet to be formally describedto science. For many years, they have been erroneously referred to as "œParazoanthus gracilis", and thatnon-existent species name seems to have stuck. The Parazoanthus genus is a commonly encountered member of the zoanthidgroup, and depending on the exact species may be found growing on either barerock or growing on living organisms, such as sponges and gorgonians. YellowPolyps are a beautiful golden to green-yellow colour and have soft, flutedbodies with long, thin tentacles, bearing a striking resemblance to smallanemones. They grow on rock and rubble and usually form small colonies,reproducing by budding from the base of the parent polyp. These zoanthids areeasy to keep, and soon spread across the rockwork to create an impressive"˜living carpet"™, that undulates in the current, making them an excellent choicefor beginners and experienced aquarists alike. Despite their reputation forhardiness, they will still obviously require suitable water quality in order tothrive and to prevent overgrowth from filamentous algae, which can swamp themif it is allowed to get out of hand. Placing the colony in an area thatreceives a moderate, but not overpowering, flow of water is also beneficial tostop the build up of detritus. Lighting should be fairly bright in order forthe symbiotic zooxanthellae within the tissues of the polyps to flourish,although Yellow Polyps tend to be a little more forgiving about light intensitycompared to other corals, largely because they also take tiny foods from thewater column. The lower the light intensity, the more the colony will requiretarget feeding. Once settled into a stable environment, Yellow Polyps willspread rapidly across the décor, so do allow plenty of room for the colony toexpand. If conditions are particularly favourable, they can even become a bitof a "œweed" (albeit a very pretty weed), taking over large areas of theaquarium; if this happens, you could ask local aquatic stores if they mightlike to trade in any small colonies with you, or perhaps see if any fishkeepingfriends would like some for their aquarium. These polyps are semi-aggressiveand will sting other corals in their vicinity, particularly stony corals, so doleave adequate space around them. Most reef fish and predatory invertebratestend to leave zoanthids alone due to their toxic nature, although there are oneor two exceptions that will try their luck. The exact potency level of thepalytoxin varies from one zoanthid to another, but it must be stressed thatthis particular toxin is extremely powerful and aquarists must take sensibleprecautions when handing these animals. Despite the potent chemical defences,there are a handful of pests that may try and predate on your zoanthids, suchCamelback Shrimp (Rhynchocinetes uritai),shrimps from the genera Saron and Lysmata, Sundial Snails (Heliacus variegatus), eunicid worms, andcertain nudibranch species. Due to their similarity in appearance to Aiptasia, some fish that have beenintroduced specifically to eat those pest anemones e.g. CopperbandButterflyfish (Chelmon rostratus) orTomentosus Filefish (Acreichthystomentosus), might just decide to nibble on your Yellow Polyps too, socaution and careful observation is required. It is a good idea to quarantinenew Yellow Polyps for several weeks before adding to the main aquarium, tolessen the chance of introducing any destructive pests. If this is not anoption then a 3 minute R/O freshwater dip can sometimes be useful before addingnew polyps to the display tank, although it will not be as effective as aperiod of quarantine and vigilant observation. When Yellow Polyps are eventuallyformally described, they may stay within the Parazoanthus genus or may be moved to a different (possibly Acrozoanthus or Zoanthus) or even a newly erected genus. There is much debate amongstscientists as to whether this species is actually a colonial anemone, ratherthan a coral, as it does not fall neatly into any particular genus at present.
Feeding
Yellow Polyps arezooxanthellate; that is they usually get most of their nutrition from theirsymbiotic algae. However, they also take particulate foods from the watercolumn, such as zooplankton, copepods, Artemianauplii etc and will benefit greatly from target feeding, particularly thosecolonies that are growing in less illuminated areas.
Propagation
Easy to propagate "“ YellowPolyps reproduce readily by budding from the base of the parent polyp.
