16S seqs of Ulva tank outlet: fresh seawater
The 16S_341F and 16S_805R primer pair  with added Illumina adapter overhang nucleotide sequences  were used to amplify the 16S V3V4 hypervariable 16S gene region of each sample. Post validation, PCR purification, indexing and library preparation were performed at the Next Generation Sequencing Facility (NGSF) at the University of the Western Cape (UWC), where the PCR products from each sample were used to create libraries with unique barcodes. Briefly, PCR products were purified to remove free primers and primer dimer species, whereafter dual indices and Illumina sequencing adaptors were attached to the purified PCR products using the Nextera XT Index Kit. This was followed by a second PCR purification step using AMPure XP beads, whereafter final library quantification and normalization was performed. Normalised libraries were pooled prior to paired-end sequencing (2250bp) on the Miseq Illumina sequencer, as per manufacturer protocols.