Recommendations regarding still water assays

When using either field or laboratory approaches, there are several other procedural questions that should be addressed. First, larval settlement often occurs more rapidly on surfaces that have been allowed to accumulate a natural biofilm 

Finally, larval density should be considered. It is generally not possible to use natural larval densities during experimentation, either because natural larval concentrations are not known, or because field densities of larvae are too dilute to be used for laboratory experimentation. Because of this, it is necessary to select a larval density that will provide for sufficient statistical power, while at the same time preventing larvae from becoming overcrowded to the extent that they influence each others behavior. As with the previous parameters, the ideal larval density will vary from species to species as a rule, however, it is probably better to assay larvae in a dilute rather than concentrated environment. In many studies, larval densities of 1-10 larvae/ml have been used. 

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