Like Reef-Daddy said, feed! There are studies that show a few species of bleached corals can meet almost all of thier demand for metabolic needs through feeding..some can't. The one in particular was a montipora, that when healthy got only 15% of it's nutrition through feeding, and while bleached was able to increase it's feeding to make up for the lack of zooxanthellae. Here is a quote from Andrea G. Grottoli, Assistant Professor Ohio State University Department of Geological Sciences, that I read from the Coral List at
coral-list@coral.aoml.noaa.gov.
"our paper showed
that only one species, Montipora capitata,
consumed enough zooplankton to meet all of its
metabolic demand heterotrophically when
bleached. When healthy, M. capitata met less
than 15% of its metabolic demand
heterotrophically. The other two species we
studied, Porites compressa and Porites lobata,
only met 21-35% of their daily metabolic demand
heterotrophically when they were either healthy
or bleached. In all cases, our corals were
exposed to naturally occurring zooplankton on the
reef. Thus under natural reef conditions, not
all bleached corals can meet all of their
metabolic needs heterotrophically. Under
artificially fed conditions (i.e., coral exposed
to higher than ambient concentrations of
zooplankton or brine shrimp in tanks), things can
be quite different. As you pointed out, the
fact that corals do get some fixed carbon from
zooplankton has been know for a very long
time. However, the fact that when bleached at
least one species can increase heterotrophic
feeding to meet all of its metabolic needs while
two others could not, is novel."
HTH a little, or at least provides some hope..good luck with your corals...hope you get full recovery!!
PK
