Most of the data on NRR assay has been performed on saltwater mussels (Mytilus sp.). This assay is performed on haemocytes as haemolymph (between 0.1 and 0.2 ml) is collected from the posterior adductor muscle using a 1 ml syringe containing an equal volume of physiological saline solution. Therefore, I am wondering what solution I should use instead? Will freshwater be sufficient? Thanks a lot in advance.