PhiX recommendations are based on Illumina’s recommendations:
|MiSeq||HiSeq 2500||HiSeq 3000||HiSeq 4000||NextSeq 500/550||Novaseq 6000|
|5 %||10 %||15 %||15 %||20 %||
Note: Protein libraries have lower diversity than DNA libraries. It is generally recommended to sequence DNA and Protein libraries together to increase diversity. Increased Phi-X is recommended if sequencing Protein libraries alone.