Swimming Pool Blog


Algae - the many hues and colors

by  Sean Griffin, September 02, 2009

Algae, bacteria and mold can present itself in your swimming pool in many forms and colors. Restoring your pool and getting back that healthy crystal clear blue water can sometimes become a task. The best remedy is of course prevention. Continually monitoring and adjusting your water chemistry is a must - but unfortunately an algae bloom can occur almost overnight. Some pools are prone to algae outbreaks due to poor water filtration / circulation, a high amount of contaminants and or algae deeply imbedded into your pool finish. Different types of algae have unique characteristics to consider when dealing with.

First let’s take a closer look at algae and break it down…It is technically considered any various aquatic, single or complex organism that produces their own food. They range in size from pin points to giant kelp and can be found in dirt, snow, clouds and most commonly floating on water. Another way to think of it is like their plants but with no roots, stems or leaves. The most common way to separate algae types is by color, ranging from yellow to black.

High doses of chlorine with proper water chemistry along with good filtration and the right cleaning tools can defeat most algae. Chlorine in any form is less affective when the ph is unbalanced. Proper water filtration is a must. Dead spots, or areas where water circulation is minimal will allow algae to re-bloom. An adequate filter is necessary in filtering out algae spores. Scoring the heads of green or black algae, to allow chlorine to enter the organism, is also required. A wire brush works well on plastered pools. Corner brushes will also allow you to brush up those difficult areas algae loves to hide. Once algae is killed vacuuming out dead spores and cleaning all components of pool, including cleaning equipment will help reduce the change of future outbreaks.

green algae treatGreen Algae - This form of algae is the most common. This primitive slimy seaweed like organism can be growing on your walls and floor, floating throughout the water, and leaching on to whatever is in the water. The quick fix to green algae is high doses of chlorine and proper brushing followed by vacuuming. In those hard to manage cases algaecide can be used to help destroy and prevent future outbreaks. Extreme pool algae? There may be a high presence of Phosphates in the water, providing a good source of food for our single celled friends.

yellow algae treatYellow Algae - Also known as mustard algae it has been known to be very resistant to chlorine and has the ability to live outside of water for an extended period of time. The ability to live outside of pool makes it a potential threat to re-grow and also to get transferred from one pool to another. It is the rarest of all algae and can be yellow green or brown. Most of the mustard algae infections occur when water balance is off or the water tests positive for nitrates.

black algae treatBlack Algae - Appears at first as spots on your pool walls. It is the most stubborn of all algae. Black algae can be very rough to brush off of pool surface due to its protective coating. Use of a pumice stone, putty knife or a chlorine tablet are all good tools to scrape off the heads. It can become deeply embedded in the cracks of plastered pools. Very difficult to remove, Rob likens it to Herpes "once you get it, you've got it for life" he says. Maintain it with a use of a black algaecide. For eradication efforts, draining and cleaning, or replastering, is indicated. "Bury it alive".

pink algae treatPink Algae - Not algae but is a moldy bacteria. This slimy mold makes water cloudy. It occurs near ocean waters most commonly from swimmers going from beach to the pool.  It can form sheets on the walls, or more commonly, is spotted in small crevices in the plaster or near the tile line and skimmers. Pink algae also likes to set up household inside of a filter tank. Easy to spot when cleaning grids or cartridges. Not a bad idea to bleach your swimsuits in the washing machine after returning from the beach.

Over-coming algae can sometimes seem impossible and in some circumstances you may need to drain your inground plaster pool and perform an acid wash. The acid wash will help to remove most of the roots and dead cells present in the pores of pool plaster. Changing the water will remove the microscopic "skeletons" of algae, which provides for new algae growth. Also consider changing the filter media (sand, cartridge or DE grids) to remove algae from inside your pool filter. Preventative measures such as these can save you a lot of money and headaches. For more information on Algae, visit our Algae Page, one of the most visited pages on our website!

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