To Perez et al. :

Image A looks like it has already gone through metamorphosis, as a central mouth between micrometer marks 2-5 and radial symmetry of Symbiodinium distribution in tissue. Is this image representative of all/many planula you used in your experiments? If so, the conclusions may need to be reconsidered, since it may demonstrate that in the absence of appropriate settlement cues, larvae are forced to undergo metamorphosis through time-dependent developmental signaling pathways. This may not occur in nature. Since settlement levels are low in your experiments, it may not be an indication of sediment overload that acts to block settlement, but rather the lack of appropriate settlement cues, as a result of the use of terrestrial-sourced sediment and glass walls of the petri dish with no conditioning period. Experimental design to test the effect of sedimentation on the settlement of "live" natural coral reef-sourced substrates would have been more representative of natural conditions.