janitor using water quality ph/cl2 chlorine tester level meter in swimming pool

accessories acid acidity algae alkaline analyzer anti automation care cartridge checking chemical chemicals chlorine clean cleaner cleanup composition control disinfection drop employee equipment filter filtration flocculant home hygiene investigate janitor kit limestone maintain maintenance man manual measure monitoring net occupation person personnel pool probe product professional purification quality remove resort safe service spa staff summer supplies swimming system table test tool uniformed water work worker