The salary of the mayor, councilmen and all officers and assistants holding any office created by this chapter or by ordinance shall be paid in monthly installments on the first business day of each month, and the salaries or wages of all other employees of such city shall be paid at such periods as may be fixed by the council. No salaries or wages shall be paid to any officer or employee of such city until after the same shall have been earned.

Every officer or assistant, other than the mayor and councilmen, shall receive such salary or compensation as the council shall by ordinance, provide, and the salary compensation of all other employees of such city shall be fixed by the council from time to time, as occasion may demand.

The city council of any city operating under the provisions of this chapter shall have the power and authority to provide for and pay to any member of the police department or fire department of such city additional compensation for services and duties performed by any such member over and above the usual and regular number of days and hours per week or month ordinarily worked by such member. Any additional compensation so paid shall be computed on the basis of the compensation regularly paid to such members of the police or fire department. Nothing herein contained shall be construed to relieve any such member of the police department or fire department from being subject to call for duty on a twenty-four hour basis whether or not additional compensation is paid.