Species group: Sponges
Other common names: Caribbean Blue Sponge, Blue Haliclona
Scientific name: Haliclona caerulea
This beauty is often the one that attracts “non-sponge-keepers” to the hobby. Happily, it is somewhat hardy as well…although “hardy” by sponge standards only.
The Blue Sponge is found throughout the Caribbean Sea, on the Pacific coasts of Mexico and Panama, and has been introduced to Hawaii and Guam. It is quite adaptable, encrusting rocks, corals, ship hulls and wooden dock pilings.
Appearance / health:
This encrusting species exhibits round or conical projections, and takes the size and shape of its anchoring site. Those collected for the aquarium trade are usually electric blue in color, but it may be light blue to near-white in the wild.
Exposure to air (which results in cell death) and a lack of suitably-strong currents are the most common causes of Blue Sponge deaths.
Behavior / temperament:
Sponges are stationary and feed continuously by filtering water through their bodies.
They are aggressive towards one another, corals, anemones and other sessile invertebrates, and may poison fish which attempt to eat them.
The Blue Sponge seems not to rely upon symbiotic algae, at least in most habitats; still, it would be prudent to supply strong illumination, as they thrive in bright aquariums. The water should be well-oxygenated, ammonia and nitrite-free, and in the range of 22-25.5 C (72-78 F). It is critical that Sponges be positioned such that they receive indirect flow from moderate to strong water currents. The aquarium should be provisioned with live sand and live rock, which will provide supplementary food in the form of micro-organisms.
The following water quality parameters should be maintained in order to assure long-term health: Specific Gravity (Salinity): 1.023-1.025; pH: 8.1-8.4; Alkalinity 8-12 dKH.
Blue Sponges require daily feedings of commercial liquid plankton preparations. As they can ingest only the tiniest of micro-organisms, products that provide minute particle size should be chosen. Important supplements include calcium, magnesium and marine trace elements.
Reproduction in the aquarium is by asexual budding. Free-living Sponges can also reproduce sexually.
Written by Frank Indiviglio