You wake up, look outside and notice your swimming pool is looking a bit greener than usual. This lovely hue means algae has taken up real estate in your water. There is no way you're letting algae live in your pool rent-free, so let's get rid of it!
What are algae anyway?
Algae are not quite plants, not quite bacteria, but they are constantly trying to get into your swimming pool. They hitch rides on the wind, rain, leaves, and even swimsuits wet with lake water. Algae come in many forms and names and in order of increasing difficulty to remove from your pool there is Green, Mustard, Pink (which is actually bacteria), and Black Algae. Fortunately, green algae are the most common type you will deal with in a pool or spa hot tub and are relatively easy to remove.
When you notice algae in your swimming pool, it is important to treat it quickly because algae will clog your pool filter and restrict water flow, allowing the condition to worsen faster. A full bloom could happen in just a few hours!
What to do:
- Vacuum the pool
- Brush the algae off the walls
- Test and balance the water chemistry. Usually, there is very little free chlorine present in the water.
- Follow up with an Algaecide
- Filter until the water is clear
- Add a clarifier if the water looks cloudy
What is Algaecide?
Algaecides come in a variety of formulas that can kill or prevent algae in the pool. Using algaecide after a shock treatment is a good way to kill spores that shock may have missed and prevent algae from growing back. Different types of algaecide will take care of different types of algae and some kill “pink algae” slime, which is actually bacteria. The best way to use algaecide is as a weekly treatment to prevent growth and outbreaks that would otherwise require large amounts of chlorine shock. Algaecide actually helps reduce chlorine use by honing in on algae so the chlorine can work on other issues. It is also great to use when opening and closing your pool.
Tip: Add algaecide during the day when algae are actively growing.
Types of Algaecides:
Quat is an economical method of algaecide that works as a disinfecting detergent that washes away algae, but adding too much can cause foaming, odor, and staining.
Metallic algaecides use metals like silver and copper to effectively handle algae including yellow and black types. They are the most powerful option but some can stain walls and light-colored hair.
Sodium Bromide is not technically an algaecide but can kill and prevent algae in your pool.