C# Dividi Arquivo Txt

class SQG
{
    public string Grupo {get;set;}
    public string Cota {get;set;}
    public string NoParcela {get; set;}
    public double ValorLiberado {get; set;}
}

void Main()
{
    double valorLiberadoOut;
    int counter = 0;
    string line;
    var ListReader = new List<SQG>();
    using(StreamReader reader = new StreamReader(Path.Combine("D:\\Wiz\\SQG\\ENVIO_0101_COB008_RelDistCobranca16032019.txt")))
    {
        using(StreamWriter fileFiltered = new StreamWriter(Path.Combine("D:\\Wiz\\SQG\\OutPutFileFiltered.txt")))
        {
            using(StreamWriter fileUpdated = new StreamWriter(Path.Combine("D:\\Wiz\\SQG\\OutPutFileUpdated.txt")))
            {

                while ((line = reader.ReadLine()) != null) {
                    if(counter != 0)
                    {
                        var addRecord = new SQG
                        {
                            Grupo = line.Substring(0, 6),
                            Cota = line.Substring(6,6),
                            NoParcela = line.Substring(648,3),
                            ValorLiberado = double.TryParse(line.Substring(655,9), out valorLiberadoOut) ? valorLiberadoOut : 0.00
                        };

                        if(addRecord.ValorLiberado >= 500000.00){
                            fileFiltered.WriteLine(line);
                        }else{
                            fileUpdated.WriteLine(line);
                        }
                        ListReader.Add(addRecord);
                    }
                    counter++;
                }
                reader.Close();
                fileUpdated.Close();
                fileFiltered.Close();
            }
            Console.WriteLine(ListReader);
        }
    }
}