• Swimming pool liners are vulnerable to algae growth.swimming pool image by apeschi from Fotolia.com
  
  Pool linings are made from materials as diverse as vinyl and fiberglass. Both materials are nonporous, and, if water circulation and pool-cleaning chemicals such as chlorine are not properly balanced, algae can grow on the surface of both. Algae left uncontrolled will make pool liners weak, stained and vulnerable to leaks and failure. Algae can also clog pool filters and even threaten the health of swimmers. Learn why algae develops, and treat your pool liner to prevent these problems.
  
  

Staining

• Vinyl pool liners are membranes that are stretched to fit and are held by the weight of water against the sides and bottom of the pool. Any break in the membrane will cause dirt and organic material to wash into the water, providing nutrients for algae to grow. Algae left unchecked by repair or chemicals will leave generations of decaying material on the liner. Combined with the effects of sun and bleaching chemicals, this process leaves dark, irregular stains on your once pristine pool liner. Patch all cracks and tears in the pool liner to avoid this problem.
  
  

Poor Water Quality and Odor

• Some forms of pool algae can emit strong odors as they multiply and decay, clouding the water and making it unpleasant for swimming. Shocking the water with chlorine can eliminate algae and bacteria, preventing it from creating a slippery, smelly film. The smell can vary, according to the type of bacteria, from the smell of rotten eggs to a sharp, nasty odor of dead fish. Follow instructions on pool chemical packaging to get the correct proportions for the size and depth of your pool, and ensure the water is properly aerated and filtered.
  
  

Safety and Health Concerns

• Algae growing on pool linings can create several safety hazards. One is slipping. Because pool liners are nonporous, anything on their surface will slip when weight is applied, which can pose a problem in the shallow end where non-swimmers and poor swimmers depend on traction to keep from slipping underwater. Respiratory problems can occur as algae reproduces and decays, particularly for people who have allergies or compromised immune systems. Lastly, decayed algae can cause bacterial infections if pool water is not showered off sufficiently after swimming. Even if your pool does not have visible algae growth, brush the liner once a week with a pool brush to lift up algae so the filtration system can remove it.