Hedge fund manager Man's first half profits will fall by a fifth to $215m as performance fees dwindled after a tough half for its flagship AHL fund.Funds under management have stabilised recently and the end of September were up over the previous three months to $39.5bn from $38.5bn. Man's net management fees are down, though, reflecting lower average managed funds while there will be 'minimal performance fees', with most of AHL below its high water mark. Net management fee income is estimated to be around $205m. Net performance fee income is estimated to be just $10m.Man expects to see a private investor net outflow in the quarter of $0.7bn and an inflow of $0.1bn from institutional investors. There has been a pick-up in sales($1.4bn in Q2 compared to $0.7bn in Q1), though the total net outflow for the first half was $1.6bn. Investment performance is expected to contribute around $0.8bn in the second quarter and $1bn for the first half. The acquisition of US hedge fund GLG will complete on 12 October, Man added.