U.S. Filter Corp. said its profit more than doubled in its fiscal fourth quarter, but it posted a net loss for the year because of acquisition-related costs. The Palm Desert-based company, which provides industrial, municipal and residential water and waste-water treatment systems and services, said net income for the three months ended March 31 rose to $37.5 million, or 34 cents a diluted share, from $16.7 million, or 20 cents a diluted share, a year earlier. Revenue rose 33% to $888 million from $669.8 million. However, for the full year, U.S. Filter posted a net loss of $299.8 million, or $3.13 a share, despite record revenue of $3.2 billion--compared with 1997's $1.8 billion. The loss, which compared with 1997 net income of $32.5 million, or 49 cents a diluted share, resulted from $440 million in charges related to U.S. Filter's acquisition of several companies. Without the charges, the company said net income for the year would have been $1.11 a share. U.S. Filter also said it expects to close on its $1.5-billion acquisition of Culligan Water Technologies Inc., announced in February, on June 15. Its stock was unchanged at $29.94 on the NYSE.