Right: Stylophora
pistillata is one of the
most studied corals on
the planet, and is very
adept at using a variety
of energy sources. Light,
plankton and dissolved
(in)organic molecules
are all utilized for rapid
growth.
Previous page: Menella
sp. gorgonians from the
Indo-Pacific are true
carnivores.
Photosynthesis
Although it may seem that heterotrophic feeding and photosynthesis are two
separate processes, these are in fact intricately linked. Nutrient exchange between
corals and symbiotic algae is diverse, and this is increased by extra light and feeding. Feeding stimulates zooxanthellae growth and buildup of photosynthetic pigments such as chlorophyll ( 4). This makes the coral a more effective “solar cell”
which is able to convert more light energy into chemical energy. This benefits both
the coral and the algae. Experiments have shown that undernourished corals grow
less than expected under high intensity lighting (irradiance of 500 μE/m2/s; very
close to high-power T5 fluorescent bulbs). French scientists found that this limitation can be reduced by providing extra nutrition in the form of zooplankton.
This likely occurs in the wild as well, when ample light and zooplankton particles
are available. This can be simulated in the aquarium, by providing extra plankton
in combination with T5 or metal halide lighting. Zooxanthellae also produce ex-
