I would recommend you to use the htmlrowprepared event for the conditional coloring of row.
According to the code you have written, below example can help you :
protected void GVResults_HtmlRowPrepared(object sender, ASPxGridViewTableRowEventArgs e)
{
if (e.RowType != GridViewRowType.Data) return;
int value = (int)e.GetValue("CarrierId");
if (value > 0)
e.Row.ForeColor = System.Drawing.Color.Red;
}
Reference:
Changing ASPxGridView Cell and Row Color on Condition