Proper swimming pool maintenance includes weekly chemical balancing, brushing and vacuuming. You should be cleaning or backwashing your pool filter at least monthly. While maintaining the filter you should be visually inspecting all the pool equipment for leaks and other problems. 
Is Your Pool Leaking?
The most common reason for suspecting a leak in your pool is the observation of a larger than normal drop in water level.

This water loss may not be obvious if your pool has an automatic fill device (that keeps the pool at a constant level), so keep your eyes open for other symptoms that may be leak related:

• Increased chemical demands
• Increased water bills
• Cracks in the deck resulting from settling earth
• Unexplainable evidence of water outside the pool

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