Turn off the water supply and electricity connected to the tank
Drain all water from the tank completely
Remove any loose debris, sediment, or sludge from the bottom
Scrub the interior walls and floor with a clean brush
Wash the tank with mild detergent and clean water
Rinse the tank thoroughly until no soap remains
Disinfect the tank using a safe chlorine solution
Let the disinfectant sit for the recommended contact time
Drain the disinfectant solution completely
Rinse the tank several times with clean water
Check and clean inlet, outlet, and overflow pipes
Inspect the tank for cracks, leaks, or damage
Refill the tank with clean water
Test the water quality before use
Clean the tank regularly on a scheduled basis