Pool Algae Problems - Cause Of Algae Growth In Swimming Pools

Pool algae problems are by far the most talked about complaint of many swimming pool owners and operators. Algae is plural and they are one-celled green looking marine plants that grow in pools and spas. There are several thousand species of algae that can and will populate your pool or spa.

However the most commonly encountered algae found in swimming pools/spas, is the green algae.

Green algae is by far the easiest of all pool algae to treat. You can get rid of green algae quicker than yellow algae (also known as mustard) or the dreaded black algae.

Pool algae are said to bloom considerably when they come into contact with water that offer the right conditions.

One thing to always remember here is this...algae will only develop or start growing in a poorly chlorinated pool or spa. This is why you have to maintain your pool chlorine between 2 and 3 ppm at all times. Chlorine is just one of the pool chemicals that has to be constantly maintained in order for you to control any potential pool algae problems.

Now you may be wondering if having algae in your pool or spa is dangerous! On the contrary! In fact, there are many health tablets and diet supplements that have algae as one of their main ingredients. However under the right conditions...pool algae growth can become dangerous.

This usually happens when the algae convert the natural sunlight into food; thus, releasing its waste products into the water of your swimming pool. This process will develop or cause your pool water to become the right environment, that will be the ultimate feeding ground for many harmful bacteria and other micro-organisms.

As I said before, you will not have pool algae problems if your pool/spa is properly chlorinated. But in a pool or spa that is poorly chlorinated, algae have the ability to reproduce at an alarming rate.

Because of this ability, algae can turn your clear looking swimming pool into a green algae producing pond. This is one swimming pool water problem that can happen over night. For the trained eye, you can usually tell when your pool chlorine level is not right. This is usually noticed by the hint of green and dull looking appearance of you pool water.

Types of Pool Algae in Swimming Pools and Spas

The level or type of pool algae problems that you may encounter, often depend on the color of your pool water. As a matter of fact, swimming pool algae are mostly grouped by their color. These tenacious little green marine plant colonies, need and love environmental conditions such as sunlight and temperature to bloom. You will have algae problems in areas of your pool or spa where there are:

  • Dead corners.
  • Cracks.
  • Holes.
  • Rough wall or bottom surfaces.

These various types of pool algae fall under several groups as previously mentioned. These groups include:

  • Green algae - As I mentioned earlier, this group is by far the most commonly talked about one of them all. It is relatively the easiest to treat as well.
  • Yellow algae - Yellow pool algae which is also referred to as mustard color algae can be very troublesome. It is troublesome because it can be a little difficult to treat, but it is still susceptible to most pool algae treatment.
  • Black algae - Black pool algae problems are the exception to the rule. Talk about nightmares! Black algae problems in your pool/spa are very difficult to get rid of...especially if your pool is made of plaster.
  • Pink algae - This type of pool water problem is not really an algae problem at all. In fact, it is more of a slime or fungus problem call Paecilonyces lilacinus. It will in fact produce a white slimy, pink or gray little colony which will appear very unsightly in your pool.

The Cause of Pool Algae Problems

Every swimming pool/spa operator and owner have at some point or another, battle some pool algae problems in their facilities. Algae spores constantly enter our pools and spas by several means. These include the wind, the rain, your pool equipment, and in some cases contaminated swimsuits.

Fortunately for us, (with the exception of the dreaded black algae) algae cannot develop in a pool or spa where there is an adequate amount of pool chlorine present.

This would be your effective amount of residual or free chlorine. Don't get me wrong, algae can live in your chlorinated pool water but it cannot develop there.

Whenever you begin to notice the green or black intruder in your swimming pool, it simply means that your chlorine level was at some point zero. In the case of black algae, your chlorine levels could have been at zero for two or three days.

Preventing Pool Algae Problems

With everything else, prevention is always better than cure. As a pool/spa operator or owner, we don't have any control over the environmental factors that contribute to the growth of algae. You can however, control some of the nutrients that do contribute to pool algae problems.

One way to do this is asking your swimmers to shower before entering the pool or spa. Other preventive methods that you can take include:

  • Ensure that you have a proper filtration system for your water.
  • Ensure that you have the right size swimming pool pump/s for your circulation flow. This will give you the correct turn over rate for your facility.
  • Always maintain proper water chemistry and water balance of your swimming pool. This includes all pool chemicals that are a part of your pool sanitation or disinfection.
  • Ensure that your swimming pool disinfection level (chlorine) is maintained above 1.0 ppm...3.0 ppm max at all times.

Other useful ways that you can prevent pool algae problems or algae growth, are by super chlorination and the use of a pool algaecide. You also have to ensure that your pool or spa is properly cleaned at all times.

This means that the surfaces of your pool walls have to be brushed and the pool vacuumed regularly.

Always keep in mind that...it is easier to prevent pool algae problems by preventing algae growth.

How do I Kill Pool Algae and Avoid Algae Concerns?

Once you allow algae to bloom in your swimming pool, getting rid of it can become a little tiresome.

However if you want get rid of your pool algae problems; then, you have to take certain steps.

To get your swimming pool or spa looking right again, you have to destroy the algae completely and correct your water chemistry. Some of the more common methods or steps you can take to correct this pool water problem are:

  • Balancing your pool/spa water. Be sure to pay close attention to your pH level.
  • Check your filtration system/s. Carry out any need repairs and cleaning if needed.
  • Adjust any valve or valves necessary to ensure an optimum circulation and turn over rate.
  • Have a schedule when you will super chlorinate (pool shock treatment) your pool. When you super chlorinate, you want to achieve a ppm level of 10.
  • Again, make sure that you have the wall surfaces and bottom of your pool/spa brushed and vacuum regularly.
  • Add a pool algaecide that is of commercial grade. Be sure to read the label to find out if the pool algaecide is recommended for the type of algae you have. Remember you may have green, yellow or black algae which will require different levels of treatment.
  • After adding your pool algaecide, it is recommended that you repeat your pool brushing and vacuuming daily. Check your pool chlorine level and if it drops below 6 ppm, add more to bring it back up. Remember...you want to maintain a ppm level of 10 until your pool algae problems are gone.

Now you know the truth about the appearance of algae growth in swimming pools and spas. Now you can take the necessary steps to eliminate and prevent your pool from actually turning green due certain pool algae problems.

Pool algae problems can lead to waterborne illnesses!

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