There has been a huge outbreak of Mustard Algae in the Northern Rivers this year. I don’t know of many pools that have been spared. Mustard Algae is chlorine resistant and really can’t be prevented. The only way to remove it is to treat it with a copper algaecide and even then, we have found only Lo-Chlor Tropical Algaecide and Purex Tropical Algaecide are the only ones that work.

It presents in the pool as a light green tinge and/or a yellowish/brown dust on the pool floor/walls. If you touch the dust, it will plume back into the water and turn the water cloudy.

  1.  Pour the algaecide around the pool.
  2. Brush the pool surface
  3.  Add chlorine – the Algaecide will swallow your chlorine for the next 2-4 days
  4.  Run the pool for approx. 8 hrs
  5. Turn the pool off and let it settle.
  6. Vacuum any residue to waste
  7. Backwash filter – a good long backwash to clear all the dust out.

A few points of note.

  1. Copper based algaecides can turn hair green if your hair is fine / blonde. Usually this can be removed with lemon juice, vinegar or tomato sauce.
  2. The algaecide will remove the chlorine from your pool. Keep a close eye on the chlorine levels and get it tested. You may need to manually dose it for a few days.
  3. If it doesn’t work the first time, get your copper levels tested at a pool shop before adding more. Too much copper can stain your pool.
  4. Mustard algae is very fine. Your filter may pick it up, but we have found that when your pump restarts on the next run, it will flush the algae dust back into your pool from the filter. You need to keep your filter clean to remove the algae dust.
Mustard Algae — Pool Maintenance Experts in Alstoneville, NSW