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How to clean a green pool

Here's How you can quickly clean a green pool

In this guide we’ll share strategies that have kept our own pools free of green water for a long time, at the end reading this guide you’ll be able to clear your green pool to sparkling blue in as little as 12 hours. 

Cleaning a Green Pool

Before we get started restoring your green pool back to blue lets look at why it turned green in the first place.

Most cases Swimming Pools become green when algae overgrows but the causes for the overgrowth can vary.

Why did the pool turn green?

Lack of circulation or clogged filter

When your filter and pump isn't working correctly your pool water will have issues, not only will you have algae frequently growing but you could also be breeding bacteria that discolors the water. Filters should run for a minimum of 7 hours and recommended 8 - 9 hours in the summer.

Change in temperatures

Algae thrives in warmer, humid environments, so if you've recently experienced rapid change temperatures the chemistry of the pool water will need to be closely monitored to maintain disinfectant chemical levels.

Incorrect pH balance

pH levels that are too high will not kill bacteria or algae and can sometimes cause skin irritation, but also pH levels that a too low can become too acidic and cause damage to pool surfaces, equipment and swimmers, for normal operation you should balance your pH level between 7.4 - 7.6.

Debris or organisms

Debris and other organisms can upset your chemical levels, using a pool cover will help keep out debris and organisms and also keeps the sun from supercharging the algae spores.

Insufficient disinfectant balance

A disinfectant must continually be present in the water so that it can react instantaneously with bacteria, algae and other organic matter that's introduced to the water. 

High TDS ( Total Dissolve Solids )

Total Dissolve solids ( TDS ) is the total amount of solids in the water, Pools that reach 2,000+ ppm or 4,000+ ppm for salt pools will generally become difficult to maintain. Its recommended to change the water when it reaches this.

Shock your pool

Shock (Super chlorinate) your pool chlorine levels with granular chlorine.

Piscimar Dicloro Gr better known as shock. has 55% active chlorine and is primarily used to rapidly increase the chlorine level for monthly pool shock treatments, it has a neutral pH and will not affect any of your other chemicals which makes it ideal for regular treatments.

Piscimar Ritocal Gr is chlorine without cyanuric acid (CyA), it provides 70% active chlorine and is mainly used to recover green pools or the clarity is effected, also the chlorine level rapidly lowers after treatment compared with other types of chlorine. 

Piscimar Maxiclor Gr is tri-chlorine (TCCA) with cyanuric acid (CyA) and 90% active chlorine, used for balancing the chlorine level in fresh water or after the pool has been shocked.

Piscimar Actibon Shock accelerates the recovery of green water by enhancing the effects of the disinfectant in the water it helps recover pools in 5 hours, specially suitable for pools with Chlorine Lock and high Cyanuric acid (CyA).

Salt Chlorinators normally have a super chlorinate modes that will shock the pool for 24hrs – 48hrs depending on the unit used.

Pool products give detailed instructions on how much to add, different brands have different strengths and ingredients so its important to check before adding to the water or speak with us for advice

Use algecide

Piscimar algibon

Common belief is that algaecides are only used to recover a green pool when quite the opposite is true. 

Algaecides are used to destroy the algae and prevent future growth. Using algaecides regularly will prevent the growth of algae. 

Algaecides come in various strengths some weaker and requires adding more to the water to be efficient and others stronger and require very little adding to the water.

Piscimar Algiklean is a Powerful bactericide, double action product, algaecide and rinse aid. its used as a shock algaecide when pools have already turned green or as a maintenance algaecide for salt pools. 
Add 1-2ltrs for every 100 m3 / water depends on needs.

Piscimar Algibon is a multipurpose monthly algicide with a five-effects
* Great effectiveness against algae.
* Provides a brilliant blue color to the water
* Repels insects from water
* Increases the transparency of pool water
* Does not produce foam
Add 1ltr for every 100 m3 / water per month

Pump and Filter

You’ll need to run your pump and filter continually to efficiently filter algae from the water, How depends on the type of filter and pump you have.

If you have a bag filter or paper filter it will require more time and effort to effectively clear a green pool see our guide on Cleaning a Filter Bag Pool

If you have a sand filter which is the most common filters used

  1. Shut off the pump and close valves to the pool, if you would like to learn more see our pump room guide
  2. Check your pump basket is clean and that water easily move through the basket without reduced flow (even small stones blocking the basket can have a impact on flow)
  3. Backwash the sand filter until the water runs clear, about 2-3 minutes
  4. Rinse your sand filter until the water runs clean about 1 minute
  5. Shut off the pump and return the valves to normal filter configuration
  6. Run the pump constantly until the water is clear, then return it to run a minimum of 7 hours per day
  7. Note the lowest pressure on your filter and increased flow from your suction and jet lines

Clean the pool

Depending how green the pool is you may need to vacuum the pool to clear the water.

Regardless if you can see the bottom or not you should vacuum the pool to remove as much debris and algae as possible the more algae on the floor and walls the harder your disinfectant will have to work and the more disinfectant you’ll need to add to the water costing you more money. 

Its recommended to clean your pool to waste to prevent the filter from clogging with algae and debris

Once you’ve vacuumed the pool, now its time to brush the walls and floor to remove any algae that didn’t vacuum up, be sure to brush round the jet and light fittings where algae can hide.

Finally remove any leafs and organics from the surface of the pool with a leaf net.

Once again check that your filter and pump basket is clean. 

Cloudy Water

Cloudy Pool

Once the green pool water has been cleared it will be a little cloudy 

Clarifiers are used for the recovery of cloudy water, you have several options to choose from, each more suitable depending on the pool type and issue, if your not sure which product to use contact us for free advise on the best product to use on your pool.

Piscimar Ultra Clear rapidly recovers cloudy water by enzymatically removing dead algae, greases and other organic matter by biodegrading them without saturating the filter. Add 0.75L / 100 m3 of water.

Piscimar Flocunet is a floculant it eliminates turbidity by suspending particles to the bottom of the pool to be vacuumed to waste. Add 1L /50 m3 of water.

Jolly Gel are gel cubes for sand filters to increase the effectiveness of the filter, by placing 1 cube in your pump basket it dissolves and places a membrane on the filter media to catch particles that are normally too small for the filter to collect.

"Why do I still have a Green Pool"

Although rare you may find your green pool will not recover despite all your efforts, there can be several reasons for this, to best advise you we recommend bringing a fresh sample of water to our Pool and Spa Warehouse.

Problems can be but not limited to.

  • * Poor Water Circulation or Filtration
  • * High TDS ( Total Dissolve solids )
  • * Chlorine Lock
  • * Yellow or Black Algae

If your pool has a high amount of Cyanuric acid or has chlorine lock Piscimar actibon shock activates the chlorine in the water. It also eliminates pink bacteria.

Professional Pool Cleaning

Elite Villa Management pool & spa cleaning service,

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