from the blog

Green Pond Water Problem: What's Causing It & How To Solve It

Care and maintenance

Water quality

September 30, 2020

Few things are as disappointing as the water of your beautiful pond turning a horrible green color. When you have a pond, the last thing you want to look out and see is ugly green water. This problem is common and it is aggravating pond owners everywhere.

While green water is not a major problem in koi and goldfish ponds, the owner will undoubtedly be incredibly bothered when they can no longer see their gorgeous fish swimming around in aquatic bliss.

Why Pond Water Turns Green

Green water results from the growth of several single-celled algae, which live suspended in water. Algae are fueled by light and excess nutrients in the pond water. Algae typically make an appearance when sunny days increase during the spring. Algae most commonly occurs in ponds that have been constructed recently, because the water chemistry has not quite settled down. However, older ponds with more established waters are not immune to the green water curse.

The main culprit when it comes to green pond water is nitrate, which is a nutrient that forms naturally as the decaying of fish feces, leftover fish food and dead plant matter occurs. Some people use nitrate test kits, but more often than not, just cleaning out any leaves that may have fallen into the pond, maintaining plant foliage, using Eco-Block Family Products and not overfeeding your fish will make a huge difference.

Keep Your Water Clear

To control algae in your garden pond you need to do the following. It depends greatly on whether the water in the pond is re-circulated with a pump, or if the pond is still.

  • Re-circulate water with a pump, mechanical filter and bio-filter
  • Shade the pond if you don't have plants
  • Use of chemicals, such as algaecides, will kill off algae, but it will harm aquatic plants also.
  • Include pond plants that will establish themselves and take over from algae
  • Use bales of oat hay or barley straw in the water where it will break down gradually to eliminate algae
  • Keep good bacteria population high
  • Add EcoBio-Block pond products containing beneficial bacteria to rid the pond of the nutrients necessary for algae to thrive

EcoBio-Block is infused with beneficial bacteria and keep beneficial bacteria population high which not only helps to control algae problems, but reduces the need for frequent maintenance.

If you have a pond with water which is re-circulated, you can control algae with the installation of an ultra violet clarifier. Ultra violet clarifiers have become increasingly popular within the past few years because they are not only effective, but also easy to install.

When you use ultra violet clarifiers in conjunction with either a mechanical or a biological filter, it will kill the algae. In addition, it will also eliminate bacteria as well as a number of harmful fish parasites. Ultra violet clarifiers also help to clear cloudy water in your pond.

Although your fish may enjoy the shade that green pond water provides during the hot summer months, no pond owner should have to miss fully enjoying his or her pond all season long.