The Problem

In November 2020 we were commissioned by Friends of Bengal and World Water Crisis to propose solutions to treat a lake covered in Lemna (Duckweed). A dense cover of duckweed on the surface of water inhibits both oxygen entering the water by diffusion and the photosynthetic production of oxygen by phytoplankton because of the poor light penetration. The water becomes largely anoxic, which in turn favours DE nitrification.

The Solution

Following the initial tests Bio2pure™ recommended application of its Aqua Culture Management® treatment to be dosed through over a period of 10  days. During the operational stage Bio2pure™ visited the site daily assessing progress of the treatment, collecting samples as per the pre-defined schedule and closely monitoring the impact of the solution on the lake.

The Result

After 8 days the appearance of the pond and clarity of water had improved dramatically.

  • Ammonia reduced by 90%
  • Phosphate reduced by 90%
  • Clarity improved by 75%

As a result of the success of the initial treatment Friends of Bengal and World Water Crisis are raising the money required to fund the on-going treatment of the lake.

Barasat lake prior to treatment

Duckweed starting to die during treatment

Members of our team working with the support of the local community throughout the treatment period

Water sample prior to treatment

Sample after 8 days (drinking water on the left for comparison)