Coloured Water

Your pool water is coloured: brown, reddish or black?


When your pool water takes on a brown, reddish or black colour, it is highly likely there is a presence of iron or manganese in the water. These elements are often present in well or borehole water. Using this type of water to fill your swimming pool may cause your pool water to take on a brown, reddish or black colour.

If your water becomes coloured, it needs to be treated quickly to avoid discolouring your pool’s surface coating and equipment.



  • Check and readjust the pH to between 7.0 and 7.4 with hth® pH PLUS or hth® pH MINUS
  • Use a metal sequestering agent such as hth® METALSTOP
  • If necessary, apply a liquid flocculant such as hth® RAPIDFLOC®, with the filter switched off during 12 hours then vacuum the deposits by sending them to the waste without going through the filter
  • If needed, use mains water to top up your pool