this is the same PM i sent you.
sure, with most corals i would say no worries, but with sps it might be a concern. halimeda is a caulerpa, not as aggressive as most, but still comes with all the same risks including sexual reproduction. the toxins are in the tips of the thallus, why fish dont eat it. if a peice breaks off best to remove it ASAP so it doesnt release anything.
here is some good info on it, look at page 12-14, its in pdf form.
http://www.diva-portal.org/diva/getD...__fulltext.pdf
this is a good one too, but its on a possible new discovery about halimeda containing bacteria that causes coral disease.
http://www.practicalfishkeeping.co.u...m.php?news=449
here is quote from here
Halimeda: The Cactus Algae by Kirby Adams - Reefkeeping.com
but the first link has more info.
Quote:
Halimeda go a step further to ward off aragonite-munching herbivores, such as parrotfish, by synthesizing noxious and potentially toxic secondary metabolites. The aptly named halimedatrial and halimedatetraacetate are diterpenoid compounds that appear to give Halimeda an extremely noxious taste and could prove toxic in large quantities (Paul and vanAlstyne 1988).-this is old but new info comfirms their thoughts on it.
hope this helps.