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Genus Rhodactis: Oral discs covered by pseudotentacles that are typically branched. Edges of discs often have toe-like tentacles. Generally there is a clear of tentacle area around the mouth.
Selection: General to Specific:
As with their close relatives, choose specimens that are fully open with no visible dead, whitish, (missing) material. Coral anemones are collected with a substantial chunk of limestone "rock". The piece snapped-off must not have torn too much of the colony asunder.
Though marketed as single versus multiple polyp "pieces" for the purpose supposedly of lowering cost per sale (?), my strong preference is for the latter. Do not be concerned that the individual polyps may be differently marked as this is quite normal. Similarly, be aware that they change shape cyclically during light/dark/feeding et al. conditions.
Healthy individual's whose Zooxanthellae are in decline should be avoided. These necessary endo-symbionts are the majority of the color seen, so select for well-colored specimens.
Corallimorpharia are one of the exceptions regarding whether to gamble on just-arrived shipments, develop a wait-and-see or deposit-and-wait stance. The sooner a desired specimen is put in an appropriate (particularly concerning lighting) environment, the better for it's health and color. Some author's suggest isolation and antibiotic treatment regimens to reduce the possibility of fouling. In the course of handling several hundred specimens I have found this to be unwarranted.
Corallimorpharia are found in areas of poorer water quality than many true corals. This fact has been proposed to explain their greater tolerance of hobbyist-generated/allowed pollution. They are found in shallow tropical seas in moderately lit and non-turbulent conditions.
Some general water quality control limits to be monitored: Maximum nitrates 30-40 ppm, minimum pH 7.8, min.-max temp. 72-85 F., negligible ammonia, nitrites, min. water density 1.020...
Lighting is important. For folks with fluorescents only, place your false corals near the surface. For metal halide, halogen users deeper placement is suggested. Too little light results in specimens' polyps losing color and cupping-up in shape. If you cannot increase intensity, extending photoperiod to may help. I'll even "plug" for actinics this time/place.
Unlike leather, et al. corals, coral anemones do not do well in strong currents. Direct power heads etc. not in their direction.
Most specimens are collected from the Caribbean (Rhodactis, Ricordea) and the West Pacific. Cold water species, like our local Corynactis californica, it should go without statement must be kept in "chilled" systems. They will eventually dissolve in warm waters.
Some species have fluorescing tentacles! Check this out under actinic lighting. Gorgeous.
Simple enough. Even minimalist approaches of common undergravel systems have met with success. Suit yourself.
Place new specimens, sans shipping water a good three inches from other tank-mates and allow for a few to several days for the new-comer to adjust to new conditions. Don't be too anxious to adjust the specimen's orientation for a couple of weeks.
All the typical coral eating and bothering organisms are eliminated; triggers, puffers, large angels, Seastars, urchins...Additionally, be careful in placing other stinging-celled animals near. Mushroom anemones regularly lose out in encounters with bubble-corals and tube anemones.
Is accomplished sexually and asexually as per corals. The regenerative properties of the group are highly touted. There are several reports of individuals torn in half both growing anew. Splitting (schizogyny) and budding are recorded from the wild and captivity.
They don't strictly speaking. During peak growth/reproduction asexually, polyps may float off and re-attach where they deem suitable.
Feeding/Foods/Nutrition: Types, Frequency, Amount, Wastes
Mushroom anemones are obligate symbionts with their Zooxanthellae. They must utilize endo-symbiotic dinoflagellates for food production and waste elimination. Additionally, all species filter feed to some extent, the longer the tentacles, the more. Their short tentacles enclose stinging cells (nematocysts) and sticky spirocysts.
Delbeek cited Achterkamp's description of stroking a polyp and observing it's reaction as a guide to willingness/necessity of feeding. The individual will form-up into a cup if desirous of further feeding.
For what it's worth, I'll reiterate my admonition concerning over-feeding. Don't do it!. Mushroom anemones have been kept for many month's without "augmentative" feeding, receiving nutrition through photosynthetic/chemosynthetic activity. Occasionally some "macro" (that is "see-able") food may be offered by placement on the polyps or sprayed in their general direction. Leave no excess.
Disease: Infectious, Parasitic
Found no specific references regarding disease with these animals; however, stressed out animals will exhibit a folding in of the body with tentacles everted. Look to water change, lowering light and/or circulation (or moving the specimen to reduce the same).
For the most part, Corallimorpharians are either alive or outright dead without much apparent warning. Almost all losses can be traced to poor water quality, maintenance on behalf of the aquarist.
Mushroom corals are either the hardiest group of cnidarians or close runners-up. They can be easily maintained in "standard" or reef-type marine aquaria, are hardy, undemanding, very good choices for beginning to advanced hobbyists. All they ask for is iodine supplementation without too much light or strong current.
Brockman, D. Undated. Disc or carpet anemones in the tropical marine aquarium. Aquarium Digest Intl. #32, Tetra.
Colin, Patrick L. 1988. Marine invertebrates and plants of the living reef. T.F.H. Publ., Neptune City, NJ.
Delbeek, Charles J. 1987. The Care and Feeding of Mushroom Anemones, Suborder: Corallimorpharia. FAMA 10/87
Elliott, Cook, J. 1989. Diel variation in prey capture behavior by the Corallimorpharian Discosoma sanctithomae: Mechanical and chemical activation of feeding. Bull. Mar. Biol. Lab. Woods Hole; vol. 176, no.3 pp. 218-228.
Gutierrez, Santiago. 1991. From a reef's point of view...Corallimorpharia...Ricordea florida. FAMA 2/91
Gutierrez, Santiago. 1993. From a reef's point of view... Rhodactis sanctithomae. FAMA 11/93.
Haywood, Martyn. 1989. The Manual of Marine Invertebrates. Tetra Press, Morris Plains, NJ.
Mancini, Alessandro. 1992. Breeding the Corallimorpharians in the marine aquarium. FAMA 10/92.
Straughan, Robert P.L. 1975. Keeping live corals and invertebrates. A.S. Barnes, S. Brunswick.