Pineapple Coral: Blastomussa merleti


Phylum: Class: Order: Family: Genus: Species:
Cnidaria Anthozoa Scleractinia Mussidae Blastomussa B. merleti

Common Names:  Blasto coral, Pineapple coral

Scientific Name:  Blastomussa merleti  Frequently seen written as Blastomussa merletti

Veron Corals of the World:
Characters: Colonies are phaceloid to plocoid, and consist of a few to large numbers of corallites.  Corallites are less than 7mm diameter.  Septa are mostly in two cycles of which only the first reaches the Columella.  Septa have slightly serrated margins.  Primary septa may be exsert.  Columellae are poorly developed.  Mantles, but not tentacles are extended during the day and may form a continuous surface obscuring the underlying growth form. Color: Commonly dark red with conspicuous green oral discs.  May also be pink orange, brown or uniform dark grey with white margins to primary septa. Similar species: Blastomussa wellsi, which has much larger corallites with more numerous septa.  See also the faviid Parasimplastrea sheppardi which is cerioid and has extensive ‘groove and tubercle’ formations.  Habitat: Reef environments, especially where the water is turbid. Abundance: Uncommon.

B. merleti has moderate sized fleshy polyps that typically cover the skeleton structure when fully expanded.  The polyps are typically in the range of 1/4″ to 1/2″ in diameter and extended day and night.  Tentacles are only extended at night.

B. merleti coloration is most commonly a medium to dark red color with a green or grey colored oral disk.  In some cases the green oral disc coloration can constitute the majority of the color of the coral though the tentacles are typically always a shade of red in color.

Wild colonies in the hobby are generally smaller fragments of a larger parent colony.

The other Blastomussa coral that may be confused with B. merleti is Blastomussa wellsi.   B. wellsi has significantly larger polyps and exhibits more color variations than B. merleti.

Natural Environment:
Found over much of the Indo-Pacific region.  They typically live in reef environments especially where the water is turbid.

 B. merleti is a fairly hearty coral when provided with the proper tank conditions outlined below.

 B. merleti prefer moderate lighting and will tolerate relatively dim lighting.  These corals should not be exposed to intense lighting.  If lighting is too intense, they should be positioned with the polyps facing out rather than up or should be shaded by another coral or rock.

Water Current:
Prefers low to moderate water motion.  They should not be exposed to strong water currents.

Fairly low.  B. merleti can sting, but does not possess sweeper tentacles and are fairly slow growing so they do not encroach on their neighbors very fast.

B. merleti are photosynthetic which will take care of most or all of their nutritional needs.  They will also take small meaty foods such as small Mysis shrimp or cyclopeeze and may benefit from an occasional target feeding in the evening when the tentacles are apparent.  This will mostly serve to increase the speed of growth of the coral.  Food can be target placed anywhere on the polyps and the tentacles will move it to the mouth.    It may be helpful to temporarily reduce the water motion during feeding so that the food can be more easily transported to the mouth.

Supplements & Water Chemistry:
Salinity should be maintained between sg 1.024 and 1.026.
Alkalinity should be maintained in the dKH 8-12 range
Calcium should be maintained at 400 ppm or higher.
pH should be maintained between 8.0-8.4

Does well within a range of at least 74º to 84º F

Tank Positioning:
Best positioning is in a low to moderate water flow  and low to moderately lit area of the tank.  The sand bed or rocks at the bottom of the tank are generally the best place to find these conditions.  If placed on the rock work, use underwater epoxy if necessary to ensure that they are securely fastened to prevent toppling.   You may want to ensure that they are happy in the location first before permanently mounting them.

B. merleti are fairly easy to propagate since the polyps are separate and the skeleton can be relatively easily broken using cutting pliers, dremel tool with cutoff wheel or similar device to separate one or more polyps to form a new colony.  The smaller specimens shown here are all captive raised from frags. 

Most larger colonies in the hobby are wild caught, but captive raised smaller frags are frequently available.  You just have to be patient as they are relatively slow growers.

All photos by ReefCorner © All Rights Reserved