This can be caused by a number of things. Here are some factors which contribute to high chlorine consumption:

- High bather load
- High water temperature
- Use of Un-Stabilized Chlorines or Stabilizer Level is Low
- Improper Water Balance
- High pH

TREATMENT

1.) Test water for all factors (including stabilizer/conditioner) and adjust to balance the water

2.) If the pool is exposed to sunlight, use a stabilized chlorine or add stabilizer/conditioner (cyanuric acid).  Initially add enough to bring the concentration up to 30 PPM.

3.) Verify that the chlorinator is working properly.  The proper level of chlorine is 1 to 3 PPM for pools, 3 to 5 PPM for spas.