 The study compares the results of EDNA meta-barcoding of multiple trophic levels from individual seawater samples collected from a kelp forest in Monterey Bay, California. The goal was to establish methods for future cross-trophic level EDNA analysis. Triplicate 1L water samples were filtered using five different 47mm diameter membrane filters and DNA was extracted from triplicates of each filter type using three widely used extraction methods. Each DNA extract was amplified using PCR primers for the 16S-RRNA gene, micro-organisms, 18S-RRNA gene, phytoplankton, and the 12S-RRNA gene, vertebrates. The study found that there were no significant differences in richness or community composition of microbial, phytoplankton, and vertebrate OTUs between any of the filter types extracted with the Dnesi or Mobio kits. However, phenol-slash-chloroform extraction resulted in significantly different community structures. The study recommends using any combination of either Dnesi or Mobio with PS, PCTE, PVDF, or NC filters for a cross-trophic level comparison. This article was authored by Annie Jurlis, Jesse Porte, Colin J. Klosek, and others. We are article.tv, links in the description below.