Samples were collected by niskin at depth, and filtered in series through five nylon mesh, and then a 1.2 and 0.2 micron supore filter. Nylon mesh were themselves backrinsed and the rinse water collected on 1.2 micron durapore filters. At BATS 90m there was also a sinking speed fractionation. Filters were flash frozen. At Horn Point Laboratory, samples were extracted with 10% SDS buffer with alternating hot and bead beating cycles, with two phenol chloroform wash and one cloroform wash. Samples were quantified, diluted, and a known volume of spike was added to each sample (see sample data for amounts). Samples were shipped to MRDNA for library prep and sequencing with 515FY-926R primers on an Illumina MiSeq.