elegance came off shell - Page 3

Elysia · 11/10/2009, 03:35 PM

Borneman covers a couple of different reproductive modes of corals, including various forms of asexual reproduction such as budding and fission. In each one, tissue separates from the parent colony and then begins to calcify and form a new skeleton. These forms of reproduction are thought to be responses to stressful conditions. Coral tissue may bud and separate, the coral may intentionally decalify part of its skeleton to release some of its tissue, or eject a living polyp from its skeleton. Regarding polyp bailout, note, p. 81, "There are also reports of Catalaphyllia, Trachyphyllia, and a few other genera of large-polyped stony corals releasing living tissue from their skeletons in captivity to drift and then begin the calcification of a new skeleton. Again, these incidents usually follow a period of stress. It is not known if this observed aquarium behavior is analogous to the true polyp bail-outs reported in the scientific literature."

In the section on Coral Health, Borneman again talks about decalcification and polyp bail out. In decalcification in captivity, the author states that the most common cause is the lack (in the water) of "bioavailable calcium, carbon sources, or other elements required for skeletogenesis." No mention is made of the liklihood of loose polyps to survive; only that correcting the environmental problems will usually stop the decalcification process. Polyp bailout occurs usually in response to disease or stress, and correction of the cause is necessary to halt the progression of the bailout. Settlement of the loose polyps is more likely to occur in a stable aquarium without a lot of circulation.

***My question: is there a way to tell whether the coral in question has undergone decalcification vs. polyp bailout?

Gary Majchrzak · 11/10/2009, 05:48 PM

Quote:

Originally Posted by Elysia

***My question: is there a way to tell whether the coral in question has undergone decalcification vs. polyp bailout?

perhaps check calcium alkalinity and magnesium levels

I don't think I've ever heard of a coral's skeleton called a "shell" until this thread. I guess you learn something new every day.

Elysia · 11/12/2009, 01:08 PM

Gary et al.,

With the assumption that low calcium would be decalcification and magnesium would... also be decalicification or polyp bailout?

Maybe I shouldn't be so hung up on what happened and just figure out what the stress was and fix it, but I am curious to know the difference between the two.

Gary Majchrzak · 11/12/2009, 01:32 PM

Quote:

Originally Posted by reefslugs

I bought a four year old elegance from a local reefer. It was over crowding his tank. His skin was reseated off the edges off the shell but you could tell it had been that way for quit some time.

this was due to decalcification. The situation was corrected and the coral continued to to lay down new skeleton.
Decalcification and polyp bailout are two different things. Polyp bailout is a response. Decalcification is a condition.
In what might be a separate (or ongoing) stessful condition (we don't know for sure) this polyp bailed out due to certain stress factors.

11/10/2009, 03:35 PM	#51
Elysia Registered Member Join Date: Oct 2007 Location: Central PA Posts: 1,052	Borneman covers a couple of different reproductive modes of corals, including various forms of asexual reproduction such as budding and fission. In each one, tissue separates from the parent colony and then begins to calcify and form a new skeleton. These forms of reproduction are thought to be responses to stressful conditions. Coral tissue may bud and separate, the coral may intentionally decalify part of its skeleton to release some of its tissue, or eject a living polyp from its skeleton. Regarding polyp bailout, note, p. 81, "There are also reports of Catalaphyllia, Trachyphyllia, and a few other genera of large-polyped stony corals releasing living tissue from their skeletons in captivity to drift and then begin the calcification of a new skeleton. Again, these incidents usually follow a period of stress. It is not known if this observed aquarium behavior is analogous to the true polyp bail-outs reported in the scientific literature." In the section on Coral Health, Borneman again talks about decalcification and polyp bail out. In decalcification in captivity, the author states that the most common cause is the lack (in the water) of "bioavailable calcium, carbon sources, or other elements required for skeletogenesis." No mention is made of the liklihood of loose polyps to survive; only that correcting the environmental problems will usually stop the decalcification process. Polyp bailout occurs usually in response to disease or stress, and correction of the cause is necessary to halt the progression of the bailout. Settlement of the loose polyps is more likely to occur in a stable aquarium without a lot of circulation. ***My question: is there a way to tell whether the coral in question has undergone decalcification vs. polyp bailout?

11/12/2009, 01:08 PM	#53
Elysia Registered Member Join Date: Oct 2007 Location: Central PA Posts: 1,052	Gary et al., With the assumption that low calcium would be decalcification and magnesium would... also be decalicification or polyp bailout? Maybe I shouldn't be so hung up on what happened and just figure out what the stress was and fix it, but I am curious to know the difference between the two.