Identification

• Mustard Algae Appearance
  
  Algae have over 21,000 varieties and a color scheme is adopted to identify the different types. The yellow algae, also known as "mustard algae," attach around the walls and grow underneath the shady parts of the swimming pool. These are small, single-celled plants that form thick clusters if left untreated in the pool. Mustard algae tend to look like dirt or sand in the water due to it distinct color, but may also have a "pollen-like" appearance.
  
  

Different Causes

• A Dirty Pool
  
  Swimming pools often deal with algae. Algae spores come in the pool via wind, rain, contaminated swimsuits or equipment. The algae can bloom to disatrous results from an imbalance of pH in the pool water, warm temperatures, sunshine and exposure to nitrates and/or carbon dioxide. Improper circulation, filtration and sanitation of the pool water also causes the growth and spread of algae.
  
  

Problems & Solutions

• Algaecides
  
  Mustard algae can cloud and color the water, thus ruining the appearance of the swimming pool. Swimmers can be in the pool where the algae is present, but the algae may contain pathogens like e-coli bacteria causing nausea, vomiting, severe stomach cramps and diarrhea. Filters' pores get clogged by the algae that hurt its efficiency to clean the pool water. The chlorine is also absorbed because of the algae's need for the chemical instead of fighting off possible contaminents.
  
  The solution for this problem is proper pool maintenance by having a good criculation of water to the entire area, pool filtration for 8 to 10 hours daily, vacuuming and brushing all surfaces of the pool, test the water twice a week, and lastly good water chemitry with the pH at 7.4 to 7.6, calcium hardness of 200 to 300 ppm and total alkalinity of 100 to 150 ppm. Algaecides are more often used to kill off algae. The most common ones are quats (or quaternary ammonium salts), polyquats, copper salts and colloidal silver. The amount of time to eliminate the problem depends on how severe the spread of algae is in the pool.