Green Algae On Pool Walls: How To Remove Algae Stains

Your pool walls contribute greatly to the aesthetics of your pool. Having those characteristic stains and streaks from green algae can put a dent in their contribution.

Learning how to handle algae blooms in your pool is crucial as a pool owner. Algae can be removed naturally without chemicals. However, some owners prefer to use chemicals. Whichever one that works for you, you will learn it when you read further.

Why is there green algae on my pool walls

As a pool owner, you must be familiar with the green discolorations and stains that appear as streaks or patches on your pool walls. It is a nightmare for every pool owner. You see your beautiful swimming pool losing its aesthetic appeal right before your eyes. And even having those dips doesn’t seem so enticing anymore.

In case, it was ever in doubt, what you have seen is just an infestation of algae. A certain species that will go to any length to be part of your pool ecosystem.

There are a number of reasons why you will have green algae on your pool walls.

  1. Failure to clear debris: The presence of debris such as fallen leaves, twigs, and branches in your pool is the source of algae. This debris harbors algae and can introduce them into your pool. When they fall into your pool and they are not removed efficiently, it can lead to an outbreak of algae infestation.
  2. Low chlorine levels: When the chlorine levels in your pool are low, it becomes very habitable for the growth of algae. Chlorine contributes to a high level of water sanitation and its absence or reduced presence will definitely allow algae to bloom.
  3. High water pH: High pH and alkalinity are conducive to the growth of algae. Algae feed off high pH, and if your water is consistently at that level, it can lead to an algae bloom. The high pH also makes chlorine less effective. High alkalinity prevents chlorine from functioning efficiently. At pH levels of 8 and higher, chlorine can only kill about 9% of bacteria and algae. Hence, pH disruption is quite important for algae growth.
  4. Poor filtration: If your filters are faulty or overworked, you could have an algae infestation on your hands. A poor filter ensures that algae in your pool is not properly removed. This gives it the opportunity to reproduce unchecked. This could be common, especially when the water in your pool is above the skimmer. It means that any floating algae won’t be drawn into the filter. As a result, it can’t be filtered out.
  5. Poor circulation: One of the things that encourages algae growth is stagnant water. When the water is static and not moving, you are giving it the perfect conditions to grow. This could be as a result of a lack of negligence in running your pool filter regularly. This leads to poor circulation. In a state of rest and exposure to constant sunlight, the algae can grow unchecked.

How do you get green algae off pool walls?

  • Vigorously scrub the walls: Make use of a hard bristle brush attached to a pole to remove visible algae. Ensure to brush thoroughly. This process loosens the algae up.
  • Apply granular chlorine shock to the affected areas. When the chlorine levels are okay, you can apply green algaecide. This you do according to the manufacturer’s instructions.
  • Run the pool water through a filter: Turn on your filters and allow it to circulate for 24 hours. This is to ensure that the dead algae are removed.
  • Give your filter a good backwash: You will not want your future recirculating algae back into the pool. Give your filter a thorough backwash and then ensure that it is spick and span. Make sure that all the dead algae are thoroughly washed off.

How do you clean pool walls without draining?

It is possible to get your pool walls to shine without having to drain the pool. Draining your pool completely can lead to some irreparable long-term damage. Hydrostatic pressure from the ground can cause your swimming pool to push up and end up breaking its shell. Due to this, you must be able to find alternatives to give your walls that sparkling look while your pool remains intact.

A good alternative to doing this is called a no-drain acid wash.

The first thing is to understand what an acid wash is. An acid wash, in actuality, involves hosing down the walls of your pool with an acid water mixture and stripping away the outer surface of your pool walls. This is a very effective method of cleaning your pool walls and giving them back their shiny look.

But as mentioned earlier, draining your pool has some ugly consequences. As a result, you wouldn’t want to use this option of acid wash. Hence the no-drain acid wash.

The no-drain acid wash is a process that involves lowering the pH of your pool water to a very low level and causing it to be acidic. The alkalinity levels will be almost non-existent. Then it is followed by a vigorous series of scrubbing the walls, ending up with the same results as a routine acid wash. But the difference here is that you are not going to be draining the pool.

How to do this is outlined below:

  1. Put away all metallic equipment. You are dealing with acid here, so you wouldn’t want the acid eating away at your pool equipment.
  2. Give your pool a pre-scrub before you start the process.
  3. Turn off all the valves and fill the pool to the brim. Ensure the pool pump is properly turned off. The acidic water can damage it.
  4. Now begin to add the pH down or sodium bisulfate to the water. Remember, the goal here is to lower the pH of your water down to one. To achieve this, you must add 9 pounds of sodium bisulfate to every 5000 gallons of water. Keep testing the water till you get to pH 1.
  5. Do this process over a period of three days while vigorously scrubbing the walls during that time frame.
  6. After that period, the walls should be clean. It is now time to add your pH increaser.
  7. Add your pH increaser in 3 evenly spaced dosages. This is to avoid clouding up your pool. The pH increaser will bring the alkalinity of your pool back up. After the application of this chemical, you will find that the pH is back at a neutral level.
  8. Then you can turn on the pumps and allow the water to circulate and return to its normal level.

How do you scrub a pool wall?

Scrub thoroughly with your brush from the water line up. The type of wall you have will determine the kind of brush you use.

For a concrete or plaster wall, you can use a brush with steel bristles. You can also make use of a pumice stone.

For a tiled wall, make use of a tile brush.

Can I use bleach to clean pool walls?

Yes, you can.

Bleach is a good sanitizer and is also a cheap option. As it is readily available and easy to use, you don’t have to be an expert to use it effectively for cleaning your pool walls.

Can you put too much bleach in a pool?

Though quite rare, it is possible and that will lead to a case of over-chlorination. The excess chlorine can cause skin, eye, and lung irritation if one comes in contact with it. It is safer to always allow the chlorine levels to dissipate (when exposed to the sun) and return to normal levels before diving into the pool.

Can you vacuum algae out of a pool?

Yes, you can.

Algae most of the time floats. You can easily use a wet vac to suck off those algae that happen to be on the pool surface. For the algae that has sunk to the bottom of the pool, the vacuum can still be used. Just make sure to refill the water as the vacuum works.

What naturally kills algae?

Baking soda and vinegar are two household options you can use as natural remedies for algae.

Another method is the use of salt generators.

What prevents algae in pools?

If you want to have an algae-free pool, ensure the following:

  • Ensure the chlorine levels are at a constant concentration of 2-4 parts per million.
  • Ensure that you circulate the pool water through the filter daily.
  • Ensure that the pH of the water and other chemicals is also in balance.
  • Ensure you use a good pool algaecide on a weekly basis.

Does leaving a pool cover on, cause algae?

It can, under the right conditions. If you are making use of a solar cover, the solar cover can cause the water temperatures to be warmer, hence creating a conducive environment for algae growth.

Also, pool covers can have debris built up in them. If this debris disintegrates and is allowed into the pool, it can form food for algae.

At what temperature does pool algae stop growing?

At 40° F, most algae will stop growing. Temperatures that low prevent them from multiplying. Most algae go dormant during the winter and resume their reproductive processes once spring breaks.

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