The Council shall have the power to fix the salary of its own members and of each officer, employee and member of any department, board, or commission of the Municipality whether elected or appointed, except as otherwise provided in this Charter. Any such person may be required by the Council, from time to time to furnish bond in such sum as the Council shall determine and with such surety as shall be approved by the Mayor; and the Council may provide that the premium for any such bond shall be paid the Municipality. The compensation of the Mayor, each member of the Council, and any other elected official shall be fixed at least thirty (30) days before the time for the filing of the nominating petitions for the terms beginning on the next succeeding first day of January, and shall not thereafter be diminished or increased during such terms.