Help!  My swimming pool is green and I do not know what to do!!!  This is a question we answer every day in our store.  Pools can turn green for many different reasons;

• No or too little chlorine
• No or too little stabilizer
• The filter is not running enough or running at the wrong time
• Phosphates in the water

These are the most common ones we see in the store.  I am going to give a brief over view on how to handle each of the above situations.  The most important thing you should do is have a professional company test your water.  By having your water tested on a regular basis you can head off most problems.  

The first question we ask everyone is; When are you running your filter?  Here in Eastern North Carolina we recommend all filters to run from sun up to sun down.  10-12 hours during the day is the best practice.  We have found that some people only run their filters 3-4 hours a day or only at night because the electricity is cheaper.  These are not very good ideas as the pool water needs the filtration and chlorine in the water when the sun is out and at its hottest.  You will spend more money on chemicals keeping your water clean if the filter is not running 10-12 hours during the daytime.  Our pool runs from 10am till 8pm during the swimming season.

When we test pool water we check the following things: stabilizer (cyanuric acid), chlorine (free and total), pH, alkalinity, calcium hardness, TDS (total dissolved solids) and phosphates.  Stabilizer is one of the most important things to add to your pool water.  An analogy that I use is – Stabilizer is the sunscreen for your chlorine.  Without stabilizer in the water as soon as the sun comes out your chlorine will be gone.  If you have not added stabilizer or had it checked you need to correct that first and then do the following:  brush the walls and floor of the pool and then quad shock (4X the normal amount of weekly shock) the water.  This will kill the algae and you will turn your water a milky grey/white.  Now it is just a matter of filtering the water to pull all the dead algae out of the water.  There are products on the market to help aid this step – I suggest talking with your local swimming pool company because the type of filter you have determines what products you can use.  A product called First Aid by Natural Chemistry works great and can be used with all types of filters.

If there is not enough or no chlorine in your swimming pool you should add chlorine tabs to the skimmer, feeder or floater.  Now you should brush the walls and floor and quad shock your pool.  Sound familiar?  The only way to effectively kill green algae in a swimming pool is to shock it hard all at one time.  A pound here and there will not kill the algae fast enough and it will continue to grow and multiply.

Phosphates have become a big problem in our area.  Phosphates eat all the chlorine (no matter how much you add to your pool) and feed all the algae.  Your pool is always green no matter how much chlorine you add to the water.  Where do they come from?  Fertilizers, forest fires and the public water supply to name a few.  If you are green from phosphates you will first need to get them out of the water with a really good phosphate remover and then brush the walls and quad shock your pool.  If you keep getting a phosphate reading in your pool there are products you can use on a weekly basis to help keep them “at bay”.  Again Natural Chemistry has a great product called PhosFree that works great!

Pools turn green on the best of us.  The good news is it can be fixed and you can heed off a green pool by following a few basic rules: 1) Have your pool water tested on a regular basis; 2) Keep a chlorine tab in the skimmer, feeder or floater.  If you are using salt to sanitizer your pool keep an eye on the generator to make sure it is producing the right amount of chlorine for your pool; 3) Shock and algaecide your pool on a weekly basis.  Shock at night and add your algaecide the following morning.  We recommend salt pools to “boost” the system once a week and add algaecide once a week; 4) Run your filter 10-12 hours during the daytime; 5) Have a professional swimming pool company test your water on a regular basis.  If you follow the above steps you should have pretty water all summer long!