A method of inhibiting fouling caused by contaminants onto a metallic tubular, flow conduit or vessel in an underground reservoir or extending from or to an underground reservoir, the method comprising: (a) introducing onto a metal oxide on the metallic tubular, flow conduit or vessel a surface modifying treatment agent comprising an anchor and a hydrophobic tail, wherein either (i) the anchor is a metal and the hydrophobic tail is an organo-silicon material, a fluorinated hydrocarbon or both an organo-silicon material and a fluorinated hydrocarbon; or (ii) the anchor is an organophosphoric acid, organophosphonic acid or organophosphinic acid and the hydrophobic tail is attached thereto, wherein the surface modifying treatment agent is of the formula: R f -(CH 2 ) p -Z wherein: R f is a perfluorinated alkyl group or a perfluorinated alkylene ether group; p is 2 to 4; and Z is selected from the group consisting of: wherein R and R" are a hydrocarbon or substituted hydrocarbon radical having up to 200 carbon atom or a perfluoroalkyl group, and R' is H, a metal, an amine or an aliphatic or aryl radical; or CF 3 (C n F 2n )CH 2 CH 2 PO 3 H 2 where n is between 3 and 5, and CF 3 (CF 2 ) x O(CF 2 CF 2 ) y -CH 2 CH 2 -PO 3 H 2 where x is from 0 to 7, y is from 1 to 20 and x+y is less than or equal to 27; (b) attaching the anchor onto at least a portion of the metal oxide; and (c) inhibiting fouling from a fluid onto the tubular, flow conduit or vessel by exposing the fluid to the hydrophobic tail. (a) introducing onto a metal oxide on the metallic tubular, flow conduit or vessel a surface modifying treatment agent comprising an anchor and a hydrophobic tail, wherein either (i) the anchor is a metal and the hydrophobic tail is an organo-silicon material, a fluorinated hydrocarbon or both an organo-silicon material and a fluorinated hydrocarbon; or (ii) the anchor is an organophosphoric acid, organophosphonic acid or organophosphinic acid and the hydrophobic tail is attached thereto, wherein the surface modifying treatment agent is of the formula: R f -(CH 2 ) p -Z wherein: R f is a perfluorinated alkyl group or a perfluorinated alkylene ether group; p is 2 to 4; and Z is selected from the group consisting of: wherein R and R" are a hydrocarbon or substituted hydrocarbon radical having up to 200 carbon atom or a perfluoroalkyl group, and R' is H, a metal, an amine or an aliphatic or aryl radical; or CF 3 (C n F 2n )CH 2 CH 2 PO 3 H 2 where n is between 3 and 5, and CF 3 (CF 2 ) x O(CF 2 CF 2 ) y -CH 2 CH 2 -PO 3 H 2 where x is from 0 to 7, y is from 1 to 20 and x+y is less than or equal to 27; (i) the anchor is a metal and the hydrophobic tail is an organo-silicon material, a fluorinated hydrocarbon or both an organo-silicon material and a fluorinated hydrocarbon; or (ii) the anchor is an organophosphoric acid, organophosphonic acid or organophosphinic acid and the hydrophobic tail is attached thereto, R f is a perfluorinated alkyl group or a perfluorinated alkylene ether group; p is 2 to 4; and Z is selected from the group consisting of: wherein R and R" are a hydrocarbon or substituted hydrocarbon radical having up to 200 carbon atom or a perfluoroalkyl group, and R' is H, a metal, an amine or an aliphatic or aryl radical; or CF 3 (C n F 2n )CH 2 CH 2 PO 3 H 2 where n is between 3 and 5, and CF 3 (CF 2 ) x O(CF 2 CF 2 ) y -CH 2 CH 2 -PO 3 H 2 where x is from 0 to 7, y is from 1 to 20 and x+y is less than or equal to 27; (b) attaching the anchor onto at least a portion of the metal oxide; and (c) inhibiting fouling from a fluid onto the tubular, flow conduit or vessel by exposing the fluid to the hydrophobic tail. <EOS>