Letter to the Editor: Characterization of Pfiesteria Ichthyocidal Activity

spp.is mostly due to direct interactions of the zoospores with fishskin and gill epithelia rather than to soluble factors.” Theseconclusions are not justified, because microbial communityanalyses of control aquariums were not included and previousstudies (5, 8) that utilized similar experimental approaches andfound significant (100%) fish death attributable to soluble fac-tors were overlooked.It is known a priori that aquariums containing fish or inoc-ulated with whole sediment will develop a complex microbialcommunity. This has been previously noted for the aquariumbioassay for