BEAR FACTS Vol 2-4: This Time Of Year Most People Are Opening Their Pool

This time of year most people are opening their pool and finding that the water has Algae. Even though you followed the directions on how to close your pool to the letter. Here is some information on why and what can be do about this and how to prevent it in the future.


In most cases warm days in combination with small holes in the winter cover as well as the water not circulating is the Culprit. As rule the best ting you can do is to open your pool early spring. But we all know that most of the time the tree debris keeps us from doing this.

Another cause of Algae growth is phosphates in the water. Phosphates are basically plant food for algae. Though we are seeing higher phosphate levels in some areas this is not a huge problem yet in this area of the world. However phosphates can be treated and controlled with testing and chemicals from our lab.

WHAT can be done?

Well at this point it’s already in the water so here is how to get rid of it. Brush all the algae off the walls, (NEVER VACUUM ALGAE INTO YOUR FILTER)! Start your filter then shock your pool and start feeding chlorine like you normally would. You may need to shock more then once. What will happen is your water will turn from green to a cloudy white. The cloud is dead algae, now its time for your filter to do its job.

Run your filter as much as possible the more you run your filter the faster the water will clean up. With a DE filter you will need plenty of DE and you may need to clean your filter once or more during this process. Cartridge filters and Sand filters should run 24/7 (keeping an eye on them of course) until the water is clear. Do not backwash sand filters to often the dirtier the sand the faster it will clean the water. But you do need to keep the water moving. Pool circulation is another cause of algae growth.

After the water has turned clear it’s time to clean your filter. Then you might shock the pool again for good measure. Sand Filters may need a change of sand depending on how bad the algae problem was. Algae can start growing in the sand.


Have your water tested before you close your pool. Improper water balance, can not only cause algae growth it can damage your pool. We will tell you to keep your pool open later in the year, Even though the leaves are the main reason we are closing the pool. Keep your cover clean and replace it every couple of years. Covers go through a lot of stress during the winter with the ice and the weight of the snow. This can cause the covers weave to stretch and pull apart this will allow light into the pool.

In the early spring lift your cover and poor algaecide into your pool once the pool has thawed. We recommend the 3 month copper based algaecide.

Another thing that can be done is you can open your pool without taking the cover off. This allows you to start filtering, circulating the water and feeding chlorine into your pool. To do this you put a hose under the cover to fill the pool to the proper level then remove all the winter plugs. Attach your filter as normal and go. It is early spring and the water is cold so your filter only needs to run a couple hours a day. In most cases this will keep the algae from even forming.

If you would like more information or have any questions about any of this please ask any of your staff.