Black Algae! And how to get rid of it!

Black Algae! And how to get rid of it!

Water is a breeding ground for life. Untreated pool water can facilitate organic growth. Single celled organisms form colonies (algae), and there goes the pool party. In some cases you can have all levels right, but still grow a crop of algae. 

The topic of this discussion is on the eradication of black algae, the most stubborn variation.

Black algae has cousins (green & mustard). Typically green or mustard algae can be easily brushed, shocked and vacuumed on waste (removing the organic material and water from pool).

The dreaded black algae forms a protective layer which is highly resistant to chlorine. Brushing and shock won’t kill it! 

The following is a step by step process to;

- Break down the protective layer

- Kill the algae below

- Vacuum it out

Things you will need; 

*Note all products mentioned are hyperlinked to their product page. Buy it today!

Liquid or Granular Chlorine, Algaecide 60, Algae Terminator & an empty bucket.

  1. Test your pool water. For the first algaecide product to work, we need the water to be free of any chlorine (0 - 0.5ppm) and the pH level to be near 7.6ppm.
  2. If the water test shows anything above 0.5ppm for chlorine turn off your salt system or discontinue adding shock or chlorine pucks. 
  3. If the pH level is above or below 7.6ppm use pH decreaser or increaser
  4. Important note* If the Alkalinity shows above or below the acceptable range (80 - 120ppm) balance with either muriatic acid (lowers alkalinity) or alkalinity increaser.
  5. Brush the pool from top to bottom. Pay extra attention and effort to the areas covered with algae. 
  6. Proceed to applying ‘Algaecide 60’ as directed on the label. The amount used is dependent on the volume of water. In most cases you will need an entire 1L bottle.
  7. Wait for 24 hours to pass.
  8. Brush the pool again.
  9. Shock the pool (add granular or liquid chlorine). This next algaecide product requires the pool water to show 20 ppm chlorine & pH of 7.6 ppm.
  10. Wait 1 hour. Test the water before proceeding. If the chlorine level is not high enough add more and wait another hour, re-test the water. If the pH level is above or below 7.6 ppm, balance, and re-test in an hour.
  11. Apply ‘Algae Terminator’. Fill your empty bucket with at least 3L of ‘fresh water’ (do not use pool water). Don’t worry if it’s more than 3L. Mix ‘Algae Terminator’ with the fresh water in your bucket.
  12. Disperse the ‘Algae Terminator’ & fresh water mixture evenly all the way around the pool. 
  13. Wait 24 hours.
  14. If you have done all the above steps correctly you will have broken down the protective layer and successfully killed the black algae. 
  15. Vacuum your pool on waste (sand filters) or using a by-pass (cartridge filters). 

The last thing to mention is the root cause of algae. Often black algae starts in hidden places. For example, underneath hang over pool steps and behind lights. If you find these places to contain algae, temporarily remove them.

We trust this process has restored your pool’s magnificence. Don’t forget to invite us to the pool party. Or, better yet, share this article with a friend or family member.