Claim 1: a composition for Preventing biofilm, characterized in that it comprises: a first non oxidizing biocide mixed with a Second non oxidizing biocide, where the second Product comprises a Quaternary Amine Compound,And the first and second Biocide Product mix with a Stabilizing agent； wherein the stabilizing Agent comprises a compound of alkyltrimethylammonium biocide which is different from the second. Claim 2: a composition as defined in claim 1, wherein the composition is a solution of a single phase.Claim 3: a composition as defined in claim 1 or claim 2, wherein the first product includes a phosphonium sulphate Salt. Claim 5: a composition is defined in any of the preceding Claims, wherein the second dialquildimetilamina Product comprises a Quaternary Compound.Claim 10: a composition is defined in any of the preceding Claims, wherein the second biocide comprising a QUATERNARY AMMONIUM COMPOUND of the formula: (r u00b9r u00b2r u00b3r u2074n u207a) u2099x u207f u207b where r u00b9 to r u2074 selected independently of the Group. And hidrocarbilo c u2081 u208b u2082 u2080 consists of groups of aliphatic and aromatic groups hidrocarbilo c u2087 u208b u2081 u2081,And x u207f u207b is a counter anion selected from the group consisting of carbonate, bicarbonate, halides, etosulfatos borates, Phosphates, citrates, c u2081 u208b u2082 u2080, nitrate, carboxylate and mixtures thereof, where n indicates the number of negative charges of the counter anion.Claim 13: a composition for Water Treatment in Oilfield Applications, which comprises the composition is defined in any of the preceding claims with a mixed Corrosion Inhibitor.Claim 14: a composition for the treatment of water as defined in claim 13, wherein also includes an antifoaming Agent, chelating Agent, Antistatic Agent, a Surfactant, a Dispersing Agent, or mixtures of a scale inhibitor The same.Claim 15: a production process for a Water Treatment composition for applications in Oil Fields, wherein the composi
