Each trustee shall receive an amount to be fixed by the board of trustees for each day’s actual attendance at the meetings of the trustees and actual and necessary expenses incurred while engaged in official business under an order of the board of trustees. No trustee shall, however, receive more than twenty-five dollars ($25) for each meeting attended, nor more than twenty-five dollars ($25) in any calendar month for attendance of meetings. The secretary may but need not be one of the trustees or may be the secretary of the district or any other person.