The browning of corals in closed systems and in the wild seems a bit confusing to me. Symbiodinium (zooxanthellae) excess seems to be the final common pathway to coral browning. I presume the zooanthellae are present in too great of numbers (hyperplasia) ratherthan increase brown pigment of the zooxanthelllae. What are the causes and mechanisms by which the zooxanthallae are induced to divide and multiply? Low lighting might be a cause...simuliar to plants low light leads to increase in chloroplasts and larger leafs. What other causes are known? Is there any basic science regarding the interaction between the Cnidiarian and the Symbiodinium? For example a coral is being irritated by excess particulate matter (i.e. low flow) causing the colony to secrete mucous and therfore increasing its' energy needs. Is there any "signaling" to the zooxanthellae to increase their numbers?
There are many other basic science questions to ask in this regard...and also better thought out and organized. I thought the question and answers may have applications to the hobby.
There are many other basic science questions to ask in this regard...and also better thought out and organized. I thought the question and answers may have applications to the hobby.
