Review title is Optiphen Plus - NOT Germall Plus [SEP] Optiphen is pretty good as a preservative and similar to Germall, but they are not the same. If I order Germall, I want Germall. Do a little research online. They are mostly interchangeable, but there are slight differences in the suggested ph range, max temp, and max usage.<br />Germall ingredients: Propylene Glycol, Diazolidinyl Urea, Iodopropynyl Butylcarbamate<br />Optiphen ingredients: Phenoxyethanol, Caprylyl Glycol