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Soapy, sudsy & phosphorus free detergents

Liquid detergent

You will need:

  • ~9 L water
  • 1 bar grated generic laundry soap or 1 cup of soap flakes
  • 1/2 cup washing soda
  • 1/2 cup borax


Option: essential oils such as tea tree, lavender, eucalyptus or rose oil

Melt 1.5L of water and soap in a saucepan until completely dissolved. Stir in washing soda and borax and remove from heat. Pour mixture into a large bucket and add remaining water. Stir and leave to cool. Use around ¼ cup per load, more for top loaders. Again, maybe use commercial detergent if you want to be careful with your good clothes.

Concentrated washing powder

You will need:

  • 4 cups grated laundry soap or soap flakes
  • 2 cups borax
  • 2 cups washing soda


Mix the dry ingredients well and store the detergent in an airtight plastic container. Use about two tablespoons per wash, or three for top loaders. Note this detergent will not make suds, but it still washes your clothes. Of course, if you want to be careful with your good clothes use commercial detergent.
soap bubbles

Why Does This Happen?

Toxic algal blooms are caused by nutrient run off from household and agricultural use of phosphorus-containing compounds such as detergents and fertilisers.

Biological slime formed by these toxic blooms comes from millions of microorganisms combining to create a gooey mass. Algae and “blue-green algae” – actually cyanobacteria – are the culprits, and can form oxygen-inhibiting blooms in lakes, rivers, dams and the ocean. These blooms have played a significant role in the evolution of life. In fact, algae have flourished for 2.7 billion years, and are currently thriving in the conditions created by warming, nutrient-rich waters, at the cost of more complex organisms such as corals and fish. In November 1991, an estimated 1000-kilometre stretch of the Barwon and Darling rivers in New South Wales gained the dubious privilege of hosting the world’s largest recorded blue-green algal bloom. A state of emergency was declared and drinking water had to be brought in to the area. It was reported that from the air it looked “like a long ribbon of pea soup.”

Scripps Institution of Oceanography, at UC San Diego, who late last year warned of the “Rise of Slime” due to a combination of climate change, ocean acidification and excess nutrient run off. 

Be Amazing Book Front Cover; Ben Newsome, teacher & founder of Fizzics Education. Be Amazing -how to teach science the way primary kids love
Be Amazing!
How to teach science, the way primary kids love

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