Reducing iron in an artificial pond

Reducing iron in an artificial pond


We would like to share an interesting experience in reducing iron and other mineral impurities from an artificial pond.

There  is an artificial reservoir with an area of about 0.8 hectares, on the restaurant and hotel complex “Knyazhy Dvor” territory, which is replenished with water from a well. The manager outlined the problem: guests who are resting and fishing in the “Knyazhy Dvor” make comments about the state of the water in the pond.  Therefore, I would like to clean the water, make it more transparent, natural and attractive in appearance.

At the end of April 2020, we installed a 1.5 kW aerator at the facility and took the first water samples for analysis.  He showed critical data on the iron content: exceeding the permissible standards by almost 2 times and the boundary content of manganese.

Reducing iron in an artificial pond
Little info

Increased iron content in water is a common problem among artificial pond owners.  Iron – one of the most common chemical elements in nature, is found in underground soils and groundwater.

In the central regions of the country, iron is found in almost all water horizons.  Its concentration varies from 0.5 to 8 mg / l with a sanitary standard of 0.3 mg / l.

8 days after starting the device, we arrived at the site again.  They explained to the manager the reason for the unattractive appearance of the water – the high content of iron and manganese impurities.  We discussed the options for solving the problem and came to the conclusion that the aerator should work for at least another 2-3 weeks.

And, of course, not everything went smoothly – the atomizer broke.  At first, we sinned on the pond, but it turned out that the spray was not ready for our pressure loads.  We have learned from this experience and are now using proven, reliable sprayers.  You can watch a video of how we tested and selected sprayers on our GreenStream Youtube channel.  (

To track the dynamics of changes in the composition and assess the efficiency of the aerator, a second water sample was taken for analysis.  It showed a decrease in iron and manganese impurities, and the color of the water objectively changed: the yellowish tint almost disappeared, and a natural dark green appeared.

Let’s be honest, we were excitedly waiting for the results of the next analysis!  After three weeks of operation of the aerator, we took samples for the third time, and the figures pleased us – all the data corresponded to the norm.

Measurement chronology:


 Iron, mg / dm3Manganese, mg / dm3
(aeration start)
0,5 (standard<0,33)0,1 (standard<0,13)
01.05.200,4 (standard<0,33)0,086 (standard<0,13)
08.05.200,31 (standard<0,33)0,056 (standard<0,13)

As you can see, the aerator in the Knyazhy Dvor reservoir has shown high efficiency in solving the problem of water quality, specifically here – exceeding the norms of iron and manganese impurities.  We provided the manager with all the results of the analyzes and explained that water from the well will inevitably worsen the appearance of the reservoir again, if the problem of impurities is not solved systematically.

Green Stream Team

Reducing iron in an artificial pond
Little info

Methods for pond cleaning from an iron impurities

The choice of methods for purifying water from iron depends on the form in which this element is contained in the water.  In Ukraine, ferrous iron is most often found.

Iron removal by ion exchange

Based on the exchange of iron ions for sodium ions.  Not always effective as catalytic resins only work up to a certain level of iron in the incoming water.  If the iron content exceeds 3 mg/l, ion exchange will be disrupted and the resin will quickly lose its quality.

Iron removal by reverse osmosis

A membrane in a reverse osmosis system removes ferrous iron in water more efficiently than an ion-exchange resin, since the filter pores are several times smaller than iron ions.  The membrane is not clogged, and all sedimentary impurities are discharged into the sewer.  The reverse osmosis system does an excellent job of cleaning iron, the level of which is no more than 10 – 15 mg / l.  A high content of ferric iron can damage the filter.  Therefore, mechanical washing filters are used to purify water from ferric iron.

Iron removal by aeration