Seachem NeoPlex (Broad Spectrum)NeoPlex Broad spectrum antibiotic effective against most external infections Safe for marine and freshwater Minimal impact on bio filter Overview NeoPlex is a broad spectrum antibiotic effective against most external infections of both marine and freshwater fish. Used as directed, NeoPlex will not discolor the water or damage the filter bed. It is well tolerated by invertebrates, although delicate species may be stressed. Active ingredients: neomycin