Nobody is happy when their pond water turns green, or when masses of thick green algae erupt from seemingly every surface in your pond. You work so hard to keep your pond clean, clear and looking good, but even with the best efforts, algae can appear in a flash. Sunlight and high nutrient levels are the perfect combination for growing algae. Future algae outbreaks can be prevented by addressing water chemistry issues such as the presence of high phosphates, high nitrates or other organic nutrients with water changes and chemical filter media. Sunlight can be limited with shade, surface covering plants, and even water dyes. While these underlying causes should certainly be addressed to eradicate and prevent future algae outbreaks, they will not be a fast cure for your algae problems.
To take care of an existing Pond Algae problem you may need to take a more aggressive approach. There are numerous products for pond algae control
(both natural and engineered) on today's market to help you rid your pond of annoying nuisance algae. When you reach the point that you are thinking about using an Algaecide, it is important to know how to use them correctly to ensure that you are using the best product for your situation.
The first thing to know when applying any treatment is the size (volume) of your pond. Overdosing, particularly with chemical algaecides, can be lethal to pond animals and plants. Calculate the volume of your pond with these formulas: Rectangular ponds - Length x Width x Average Depth x 7.5 or for round ponds - 3.14 x (radius)2 x Average Depth. Make sure that all of your measurements are in feet. For oddly-shaped or angular ponds calculate using the surface area x the average depth, or calculate the volume of small areas and add them up. Once you know how much water you have to treat, you'll be on the way to successful algae control.
Next you'll want to explore the various types of algaecides and algae-fighting treatments available to find one that will suit your needs. What kind of algae are you fighting? Do you have livestock in your pond, or do pets and other animals drink from the pond? Do you have ornamental plants in the pond that may be affected by the treatment you use?
Try Alternatives to Algaecides First
Natural solutions including barley straw products
, biological additives and fish safe water dyes may be the first options to explore. As the lignin in barley straw biodegrades, natural compounds act as oxidizers to combat algae. This process happens over time as the Barley Straw breaks down. Barley pellets, extract and other variations work the same way, but faster, as the compounds are more readily available in these forms. Biological additives
boost bacterial that help to digest muck in the pond, reducing nutrients that feed algae. Water dyes
and tints block the sunlight and prevent algae from forming and taking over. These methods allow for continuous control, simply replenish the straw as it degrades and the dye as it fades to keep algae in check.
When Taking the Conservative Approach Doesn't Work
For ponds already overwhelmed with algae, free-floating algae blooms or algae on tough to reach or clean surfaces like rocks and equipment, it is time to turn to an Algaecide to help you get your Pond Algae problem under control. There are a few different types of Algaecides that are available for your pond. Algaecides for planted ponds
are generally formulated with oxidizing ingredients that destroy algae on contact or chemical ingredients that break down cell walls of simple alga. These treatments are typically safe for fish, ornamental plants and other animals in and near the pond provided instructions are followed. Algaecides for non-planted ponds
often contain copper as the active ingredient which has the potential not only to kill plants, but is also harmful to snails and other organisms in the pond. If you have an advanced free-floating algae issue (if your water is green like pea soup) you may consider adding a UV sterilizer
Manual removal of as much algae as possible before treatment is highly recommended to allow algaecides to work more efficiently and to prevent potential dangers for the pond after treatment. Closely follow the manufacturer’s instructions to ensure proper dosage and to take any precautions recommended by the manufacturer. Make sure you have adequate aeration and surface agitation to supply your fish with vital oxygen, especially important during the warmer months. It is best to treat early in the day when you are able to observe how your animals are responding and take steps if necessary to add more aeration should they show distress.
Remove as much of the dead algae and debris as possible when treatment is complete, so that it isn't left to decay in the pond. Once treatment is finished, a partial water change/siphon is also recommended, with particular attention to the bottom of the pond to remove the debris that may settle there. Addition of a biological "sludge remover" or bacterial supplements will help to breakdown the remaining debris to prevent water chemistry issues.
Best Solution for Green Water
The most common algae problem that pond owners confront is green water, caused by free floating green algae in their pond water. Using a UV Sterilizer or Clarifier is by far the most effective method for eradicating green water, and maintaining a crystal clear pond. The UV light produced inside these devices destroys the green water causing algae’s ability to reproduce when it is exposed, resulting in complete removal. While the initial cost may be more than the cost of an algaecide treatment, free floating algae will usually reoccur, and a sterilizer can be a permanent chemical free solution.