[Coral-List] Seeking method for analyzing DIC drawdown in calcification

[Justin]

Dear Coral List,
    I am attempting to quantify the DIC drawdown attributable to calcification of coral skeleton in corals from Bermuda.  The goal is to have corals in closed aquaria with filtered circulating water and 13C tagged DIC.  Right now the biggest problem I am encountering is acquiring only the coral skeleton that has taken up the tagged DIC.  Does anyone know of a way to isolate only the most recently grown skeleton WITHOUT also including coral skeleton that did not take up the tagged DIC?  I will be using a GC Mass Spec (Europa) to analyze the 13C of the skeleton.  Any help here would be greatly appreciated!

Justin Ossolinski
University of Delaware
Graduate College of Marine Studies