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Unless you’ve decided to turn your swimming pool into a habitat for frogs and ornamental fish then it should be crystal clear and sparkling. Green is a pretty enough colour, but not in our pool!  A green pool can happen unexpectedly, even overnight, but returning it to its healthy best is not too difficult.  We’re going to fix a green pool fast.

Algae is the uninvited guest has showed up and taken residence in your pool and we’re going to show you the steps you need to take to get this little guy evicted.

You’ve already got nearly everything we need in your pool shack to deal with the intruder. A chemical test kit, pool brush and a pool filter pump, but we do need to arm ourselves with some extra shock chemicals to deal with the pesky algae invasion in a timely, efficient manner.

Time scale for green to clean 3 – 5 days. 


  • Check your pool filter. It’s generally a good idea to install a new one and have a couple of spares available too. We are going to filter out a lot of algae through this filter so don’t be tempted to use an old worn one, you’ll end up just recycling the dead algae back to the pool. Sand filters will need a really good backwash to get started. The pump will typically need to be run between 3 and five days
  • Test the treat the pool water. Almost certainly the chlorine level has dropped below 1ppm, that’s what allowed the algae to take up residence. Now we need to balance the PH. We are looking for the high end of PH levels, around 7.9. We have written a helpful chemical treatment guide here.
  • Break up the algae.  Algae that’s attached to to the walls or bottom of the pool is harder to treat so we need to try and scrub it off and into suspension. That way our filter can deal with it. Make sense?  If your pool is so green you can’t see the bottom then you’ll just have to scrub blind. Remember for the fastest results the algae has got to be free floating not clinging to the sides for dear life!!!
  • Shock the pool.  Ok, time to get serious!  Now we’re going to see this pest off for good!! You’ll need a strong pool shock product with plenty of chlorine. We recommend looking for one with a minimum of 70% available.  Follow the product instructions and keep the pump running constantly while it does its work. The pool is going to get even more murky in the beginning of the clean up. That’s a good sign, don’t worry it’s simply the algae dying off and becoming suspended in the water. The filter is going to take care of it.
  • Keep cleaning filter.  It’s really important to keep an eye on your filter though this shock phase. Back wash regularly, daily is good. Cartridge filters need to be pulled, inspected and cleaned even more often. There should be a lot of algae coming its way and you need to prevent a pressure build up.
  • Algaecide option. You can add an algaecide as the chlorine levels from the shock drop. This can help the process but is not mandatory. We think it’s a step worth taking but really depends on the extent of the algae buildup.
In The Swim Super Pool Algaecide
4,916 Reviews
In The Swim Super Pool Algaecide
  • In The Swim Super Algaecide is perfect for spring openings and routine pool maintenance, minimizing algae growth.
  • Seeing the bottom of the pool.  At this point your pool should be looking something like a swimming pool again.  If not it needs to be re-shocked.
  • Vacuum time. Get vacuuming,  or get your old friend the robotic pool cleaner and toss him in to finish up things. We’ve written about the best automatic pool cleaners here. They are an investment you’ll not regret.  If your vacuum is struggling to deal with the fine algae particles the you can add a flocculant solution to bind them together . They’ll drop to the pool base for more efficient vacuuming.Check chemical balance.  Do a chemical test and re adjust values as required.
  • Check chemical balance.  Do a chemical test and re adjust values as required.

INFLATE YOUR PINK FLAMINGO, stock up your floating bar, and jump right in.

Cool Inflatable Flamingo
581 Reviews
Cool Inflatable Flamingo
  • {FUN DESIGN & ENOUGH ROOMS} This Flamingo kiddie pool is perfect for kids have fun in summer to against the heat and stay away from outside bacteria. Can be used both indoor & outdoor. You can take it at home or on a trip. The pool size is (63" X 47" X 35").There is enough room for two or three kids to have fun and play.



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