An algae often grown in the reef tank has been found to cause a disease in some forms of coral.
According to new research by published in next month's issue of the journal Ecology Letters, direct contact with the macroalgae Halimeda opuntia can trigger a virulent disease called white plague type II.
Nugues, Smith, Hooidonk, Seabra and Bak, claim that white plague type II, which has caused widespread deaths in Caribbean corals, often occurs simultaneously with heavy growths of macroalgae.
To test their hypothesis, the scientists exposed the hard coral Montastraea faveolata to the algae. Some of those exposed to H. opuntia developed the disease, while those that were unexposed did not.
The disease is believed to be caused by a bacterium called Aurantimonas coralicida. This was found to be present on the macroalgae, both near to, and far away from diseased corals, indicating that it acts as a reservoir for the disease.
The team believes that macroalgae are responsible for many coral wipeouts and suggest controlling macroalgae in order to save corals from white plague.
The algae is often sold as an ornamental macroalgae for the reef aquarium, however, on the basis of this research it may perhaps be wise to remove it from your aquarium now.
For more details see the paper: Maggy M. Nugues, Garriet W. Smith, Ruben J. Hooidonk, Maria, I. Seabra, Rolf P. and M. Bak (2004) - Algal contact as a trigger for coral disease. Ecology Letters, Vol. 7.